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As an elementary mode of locomotion, rotation has been ubiquitously demonstrated in macroscopic dimensions, or microscopically realized in levitated systems and hydrodynamic environments. However, it has remained an untouched research topic to achieve regulated rotation on solid surfaces at microscale, wherein friction serves as the dominant yet formidable external force. Here, this gap is bridged through an all‐optical approach. By utilizing pulsed light with an elongated Gaussian profile and twisting it relative to an illuminated object, chiral vortexes are introduced in both the optothermally excited elastic waves and the as‐induced surface friction, endowing the object with a restoring torque. Self‐regulation of the rotor and refueling of the chirality synergistically modulate the rotational motion. On this basis, orientation of the rotor can be adjusted arbitrarily by any specific angle, achieving an angular resolution of 1×10−4$1\ \times \ {{10}^{ - 4}}$ rad and rotation speed up to 10 rpm. Furthermore, the composite motion is demonstrated, combining both rotational and translational modes into the light field‐rotor system. The proposed technique extends the capability of optical manipulation on frictional solid surfaces by exploring the relation between the symmetry‐breaking condition and the modes of locomotion, which provides theoretical guidance and practical opportunities for building reconfigurable devices on solid substrates. [ABSTRACT FROM AUTHOR]

Microbots have shown considerable potential in the biomedical field. Their capability to target specific areas for diagnosis, treatment, and other applications with minimal invasiveness is particularly advantageous. However, complex application environments and harsh driving conditions greatly limit the locomotion behaviors of microbots, and therefore the locomotion mode of microbots deserves more exploration and research. This study focuses on a near‐infrared light‐driven bubble‐propelled microbot. The photothermally responsive materials used in the design are modified to enhance bubble generation properties. Additionally, the controlled 3D printing preparation process can indirectly influence the bubble aggregation pathway by altering the microbot's micro‐nanostructured porous structure. Ultimately, by adjusting the laser parameters, the microbot can be controlled to achieve a variety of locomotion modes. Furthermore, the experimental observations and theoretical analysis of the microbot's locomotion modes are summarized. A preliminary digital description is provided, which verifies the feasibility of controlling these locomotion modes. This lays the foundation for the precise control of microbots in future applications. [ABSTRACT FROM AUTHOR]

Optically controllable delivery of microparticles excites interesting research and applications in various fields because of the noninvasive and noncontact features. However, long-distance delivery with a static low-power light source remains challenging. Here, the constant-force photonic projectile (CFPP) is employed to achieve long-distance delivery of microparticles with a low-power laser beam. The CFPP takes advantage of photon absorption to create a constant optical force within a large range, surpassing traditional tweezers. The concept of CFPP has been experimentally corroborated by remote control over micrometer-sized absorptive particles (APs) using a simple tilted focused beam. At the laser focus, strong photon absorption results in a large constant optical force that ejects the APs along the optical axis. Furthermore, the additional thermal convection field, which attracts particles from a distance into the working range of the CFPP, is utilized to collect the unbound APs for reuse. Finally, we demonstrate the concept of drug delivery by transporting a small microparticle onto a host particle at a remote location. The proposed CFPP provides a new perspective for drug delivery and heat-enhanced photodynamic therapy. [ABSTRACT FROM AUTHOR]

The local force field generated by light endows optical microrobots with remarkable flexibility and adaptivity, promising significant advancements in precise medicine and cell transport. Nevertheless, the automated navigation of multiple optical microrobots in intricate, dynamic environments over extended distances remains a challenge. Herein, a versatile control strategy aimed at navigating optical microrobotic swarms to distant targets under obstacles of varying sizes, shapes, and velocities is introduced. By confining all microrobots within a manipulation domain, swarm integrity is ensured while mitigating the effects of Brownian motion. Obstacle's elliptical approximation is developed to facilitate efficient obstacle avoidance for microrobotic swarms. Additionally, several supplementary functions are integrated to enhance swarm robustness and intelligence, addressing uncertainties such as swarm collapse, particle immobilization, and anomalous laser–obstacle interactions in real microscopic environments. We further demonstrate the efficacy and versatility of our proposed strategy by achieving autonomous long‐distance navigation to a series of targets. This strategy is compatible with both optical trapping‐ and nudging‐based microrobotic swarms, representing a significant advancement in enabling optical microrobots to undertake complex tasks such as drug delivery and nanosurgery and understanding collective motions. [ABSTRACT FROM AUTHOR]

Colloidal photonic crystals (CPCs) are extensively utilized in nanoscale light manipulation due to their periodic dielectric structure. However, achieving spatial reconfigurability in CPCs remains a significant challenge, despite its importance for broader photonic applications in colloidal science. In this study, an optically induced thermoelectric field is generated by adding ionic surfactants to the solution, leading to the efficient formation of tightly assembled nanoparticles that exhibit the characteristics of CPC, which is termed optothermo‐CPC. Specifically, this CPC exhibits excellent spatial reconfigurability through the tuning of the optically induced thermoelectric field. This allows for the remote control of its position and shape, in a real‐time and high‐precision manner. Additionally, by changing the particle size, it is possible to tune the transmission spectrum and color. Additionally, optothermo‐CPC can navigate obstacles and possess a robust self‐healing ability. These highly adaptable and reconfigurable properties endow CPCs with significant potential for various photonic applications within complex fluidic environments. [ABSTRACT FROM AUTHOR]

We report a transverse optical torque exerted on a conventional isotropic spherical particle in a direction perpendicular to that of the illuminating wave propagation. By using full-wave simulations and deriving an analytical expression of the transverse optical torque for particle of arbitrary size, the origin of this transverse optical torque is traced exclusively to the magnetic part of the spin angular momentum, regardless of the size and composition of the illuminated particle. To our surprise, for a non-magnetic dielectric particle, the transverse optical torque is found to originate mainly from the magnetic response of the particle, even when the particle size is much smaller than the illuminating wavelength. This is contrary to the general intuition that the electric response of a non-magnetic dielectric particle dominates its magnetic response in the mechanical effect of light, especially in the Rayleigh limit. [ABSTRACT FROM AUTHOR]

Optical manipulation technology encompasses a suite of micromanipulation techniques that employ light to control and actuate microscopic objects. As a valuable scientific tool, optical manipulation technology is employed by researchers to investigate fundamental biological processes, examine the mechanics of microstructures, and develop innovative technologies with applications in diagnostics, imaging, and micro‐scale manufacturing. The rapid development of optical manipulation technology, combined with advanced microfabrication techniques, has catalyzed the emergence of a burgeoning research domain termed optically‐driven micromachinery. This rapidly expanding field has garnered significant research interest in recent years, fostering interdisciplinary collaboration across advanced manufacturing, materials science, biotechnology, and micro‐electromechanical systems. The capability to optically manipulate and control micromachines also opens new avenues for the development of advanced tools, sensors, and devices with enhanced functionalities, enabling the accomplishment of tasks previously considered impossible. This review presents a systematic overview of two important optical micromanipulation technologies, optical tweezers and optoelectronic tweezers, with focus on their applications in the field of optically‐driven micromachinery. A comparative analysis of optical tweezers and optoelectronic tweezers is conducted, accompanied by a discussion on strategies to further enhance their performance, paving the way for the development of more advanced and powerful optically‐driven micromachinery in the future. [ABSTRACT FROM AUTHOR]

This study introduces a novel paradigm for achieving widely tunable many‐body Fano quantum interference in low‐dimensional semiconducting nanostructures, beyond the conventional requirement of closely matched energy levels between discrete and continuum states observed in atomic Fano systems. Leveraging Floquet engineering, the remarkable tunability of Fano lineshapes is demonstrated, even when the original discrete and continuum states are separated by over 1 eV. Specifically, by controlling the quantum pathways of discrete phonon Raman scattering using femtosecond laser pulses, the Raman intermediate states across the excitonic Floquet band are tuned. This manipulation yields continuous transitions of Fano lineshapes from antiresonance to dispersive and to symmetric Lorentzian profiles, accompanied by significant variations in Fano parameter q and Raman intensity spanning 2 orders of magnitude. A subtle shift in the excitonic Floquet resonance is further shown, achieved by controlling the intensity of the femtosecond laser, which profoundly modifies quantum interference strength from destructive to constructive interference. The study reveals the crucial roles of Floquet engineering in coherent light‐matter interactions and opens up new avenues for coherent control of Fano quantum interference over a broad energy spectrum in low‐dimensional semiconducting nanostructures. [ABSTRACT FROM AUTHOR]

Actuation of micro‐objects along unconstrained trajectories in van der Waals contacting systems—in the same capacity as optical tweezers to manipulate particles in fluidic environments—remains a formidable challenge due to the lack of effective methods to overcome and exploit surface friction. Herein, a technique that aims to resolve this difficulty is proposed. This study shows that, by utilizing a moderate power beam of light, micro‐objects adhered on planar solid substrates can be precisely guided to move in arbitrary directions, realizing sub‐nanometer resolution across extended surfaces. The underlying mechanism is the interplay between surface friction and pulsed opto‐thermo‐elastic deformations, and to render a biased motion with off‐centroid light illumination. This technique enables high‐precision assembly, separation control of nanogaps, regulation of rotation angles in various material‐substrate systems, whose capability is further tested in reconfigurable construction of optoelectronic devices. With simple set‐up and theoretical generality, opto‐thermo‐elastic actuation opens up an avenue for versatile optical manipulation in the solid domain. [ABSTRACT FROM AUTHOR]

Cell migration is an essential physiological process in the life cycle of cells, playing a crucial role in cancer metastasis, neural development, and cellular immune response. However, achieving precise control of cell migration at single‐cell level is challenging due to the intricate and diverse microenvironments of cells. Here, an optical technique is presented that utilizes light‐actuated micronavigators to guide the directional migration of individual cells both in vitro and in vivo. Employing high‐speed scanning optical tweezers, micronavigators near target cells are trapped and rotated at a rotation speed of up to 12 000 rpm, which, to the best of knowledge, represents the fastest rotation of light‐driven micromotors in a biological environment to date. The micronavigators generate a powerful fluid shear force (up to 40 pN) which can guide the migration of immune and nerve cells in a predetermined direction. Furthermore, micronavigators are employed to guide cell migration in various biological systems, including lab‐on‐a‐chip devices and blood vessels within living animals. This technique offers new opportunities for controlling cell migration, enabling precise immune activation, and neuron repair at the single‐cell level. [ABSTRACT FROM AUTHOR]

Being able to quantify the phototoxicity of dyes and drugs in live cells allows biologists to better understand cell responses to exogenous stimuli during imaging. This capability further helps to design fluorescent labels with lower phototoxicity and drugs with better efficacy. Conventional ways to evaluate cellular phototoxicity rely on late‐stage measurements of individual or different populations of cells. Here, we developed a quantitative method using intracellular microtubule polymerization as a rapid and sensitive marker to quantify early‐stage phototoxicity. Implementing this method, we assessed the photosensitization induced by organelle dyes illuminated with different excitation wavelengths. Notably, fluorescent markers targeting mitochondria, nuclei, and endoplasmic reticulum exhibited diverse levels of phototoxicity. Furthermore, leveraging a real‐time precision opto‐control technology allowed us to evaluate the synergistic effect of light and dyes on specific organelles. Studies in hypoxia revealed enhanced phototoxicity of Mito‐Tracker Red CMXRos that is not correlated with the generation of reactive oxygen species but a different deleterious pathway in low oxygen conditions. [ABSTRACT FROM AUTHOR]

Chiral particles have attracted considerable attention due to their distinctive interactions with light, which enable a variety of cutting-edge applications. This review presents a comprehensive analysis of the optical forces acting on chiral particles, categorizing them into gradient force, radiation pressure, optical lateral force, pulling force, and optical force on coupled chiral particles. We thoroughly overview the fundamental physical mechanisms underlying these forces, supported by theoretical models and experimental evidence. Additionally, we discuss the practical implications of these optical forces, highlighting their potential applications in optical manipulation, particle sorting, chiral sensing, and detection. This review aims to offer a thorough understanding of the intricate interplay between chiral particles and optical forces, laying the groundwork for future advancements in nanotechnology and photonics. [ABSTRACT FROM AUTHOR]

Large‐scale particle manipulation with single‐particle precision and further flexible patterning into functional structures is of huge potentials in many fields including bio‐optoelectronic sensing, colloidal lithography, and wearable devices. However, it is very challenging for the precision manipulation and flexible patterning of particles on complicated curved and functional substrates. In this work, opto‐thermal‐tension (OTT) mediated precision large‐scale particle manipulation and flexible patterning based on soap film are reported. Flexible manipulation and subsequent patterning of particles with single‐particle resolution is realized by optothermal regulated surface tension on soap films. Reconfigurable patterning of particle structures with different shapes as well as large‐scale ordered structures (up to 2000 particles) with particle sizes spanning two orders of magnitude (0.5–20 µm) is realized using this OTT mediation method. Importantly, due to the high flexibility of soap films, the patterned large‐scale particle structures can be non‐destructively transferred to curved and rough substrates, including rough iron pipe surface, leaf and skin surface. This OTT mediated method provides a new method for precision large‐scale particle manipulation and flexible patterning with high versatility on complicated functional substrates, with great potentials for optoelectronic and biophotonic sensing and wearable device design on different curved and rough functional substrates. [ABSTRACT FROM AUTHOR]

Optofluidics is dedicated to achieving integrated control of particles and fluid motion, particularly on the micrometer scale, by utilizing light to direct fluid flow and particle motion. This field has seen significant growth recently, driven by the concerted efforts of researchers across various scientific disciplines, notably for its successful applications in biomedical science. In this review, we explore a range of optofluidic architectures developed over the past decade, with a primary focus on mechanisms for precise control of micro and nanoscale biological objects and their applications in sensing. Regarding nanoparticle manipulation, we delve into mechanisms based on optical nanotweezers using nanolocalized light fields and light-based hybrid effects with dramatically improved performance and capabilities. In the context of- sensing, we emphasize those works that used optofluidics to aggregate molecules or particles to promote sensing and detection. Additionally, we highlight emerging research directions, encompassing both fundamental principles and practical applications in the field.

Optical tweezers exploit light–matter interactions to trap particles ranging from single atoms to micrometer-sized eukaryotic cells. For this reason, optical tweezers are a ubiquitous tool in physics, biology, and nanotechnology. Recently, the use of deep learning has started to enhance optical tweezers by improving their design, calibration, and real-time control as well as the tracking and analysis of the trapped objects, often outperforming classical methods thanks to the higher computational speed and versatility of deep learning. In this perspective, we show how cutting-edge deep learning approaches can remarkably improve optical tweezers, and explore the exciting, new future possibilities enabled by this dynamic synergy. Furthermore, we offer guidelines on integrating deep learning with optical trapping and optical manipulation in a reliable and trustworthy way.

Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation of objects, ranging from atoms to space light sails. Since the pioneering work by Arthur Ashkin in the 1970s, optical tweezers have evolved into sophisticated instruments and have been employed in a broad range of applications in the life sciences, physics, and engineering. These include accurate force and torque measurement at the femtonewton level, microrheology of complex fluids, single micro- and nano-particle spectroscopy, single-cell analysis, and statistical-physics experiments. This roadmap provides insights into current investigations involving optical forces and optical tweezers from their theoretical foundations to designs and setups. It also offers perspectives for applications to a wide range of research fields, from biophysics to space exploration.

The paper demonstrates a method for calculating spiral beams of a given configuration based on a linear combination of displaced Gaussian beams. A new method for generating spiral beams is implemented. The effect of scaling the phase distribution on the quality of the generated light fields is experimentally investigated. The synthesized fields are tested in an experiment on optical manipulation of ensembles of single microparticles. [ABSTRACT FROM AUTHOR]

Converting non‐visual light into photocurrent while maintaining high visual transparency is vital for semitransparent organic solar cells (ST‐OSCs) application, yet often challenging over insufficient invisible light‐harvesting. Herein, spectrally selective optical manipulation for ST‐OSCs with high visual light transparency and full‐spectral non‐visual light reflection is proposed by matching the optical admittance of ultrathin Ag films using ZnS and MgF2. The reflection of optically enhanced ST‐OSCs at the spectral region beyond the human eye's response spectrum is improved and the transmission in the visual region is simultaneously enhanced. By further integrating an anti‐reflective structure, the optimal structure boosts the average visible transmittance and power conversion efficiency of ST‐OSCs to 44.3% and 12.6%, respectively, yielding a record light utilization efficiency of 5.6%. Corresponding flexible ST‐OSCs with high mechanical stability implies that this work provides a facile and universal strategy for ST‐OSCs aiming at building integrated photovoltaics. [ABSTRACT FROM AUTHOR]

Frankliniella occidentalis (Insecta: Thysanoptera) is a cosmopolitan species considered a major pest of ornamental, horticultural, and fruit crops. Colored traps with artificial or sunlight sources are used to monitor populations and manipulate adult behavior as a control alternative. In paired controlled trials, phototaxis of F. occidentalis was assessed at 21 wavelength combinations of 397 nm (violet), 462-463 nm (blue), 527-534 nm (green), 589-595 nm (yellow), 609 nm (orange), 628 nm (red), and white (432-618 nm) using low-cost light emitting diodes (LEDs). Females at one to two days of emergence and with four to five hours of starvation showed attraction and shorter response time to the (violet) and (yellow) combination (FP= 14, FN= 1) with an average response time of 2.763 ± 1.350 min (minimum response at 0.583 min and maximum of 4.417 min), compared to blue-green, green-violet, yellow-red, red-violet combinations. The results contribute to standardization processes for the design, implementation, and use of light traps in monitoring and control systems for Colombian populations of F. occidentalis in the context of integrated pest management. [ABSTRACT FROM AUTHOR]

Abstract This study introduces a novel paradigm for achieving widely tunable many‐body Fano quantum interference in low‐dimensional semiconducting nanostructures, beyond the conventional requirement of closely matched energy levels between discrete and continuum states observed in atomic Fano systems. Leveraging Floquet engineering, the remarkable tunability of Fano lineshapes is demonstrated, even when the original discrete and continuum states are separated by over 1 eV. Specifically, by controlling the quantum pathways of discrete phonon Raman scattering using femtosecond laser pulses, the Raman intermediate states across the excitonic Floquet band are tuned. This manipulation yields continuous transitions of Fano lineshapes from antiresonance to dispersive and to symmetric Lorentzian profiles, accompanied by significant variations in Fano parameter q and Raman intensity spanning 2 orders of magnitude. A subtle shift in the excitonic Floquet resonance is further shown, achieved by controlling the intensity of the femtosecond laser, which profoundly modifies quantum interference strength from destructive to constructive interference. The study reveals the crucial roles of Floquet engineering in coherent light‐matter interactions and opens up new avenues for coherent control of Fano quantum interference over a broad energy spectrum in low‐dimensional semiconducting nanostructures.

Abstract Actuation of micro‐objects along unconstrained trajectories in van der Waals contacting systems—in the same capacity as optical tweezers to manipulate particles in fluidic environments—remains a formidable challenge due to the lack of effective methods to overcome and exploit surface friction. Herein, a technique that aims to resolve this difficulty is proposed. This study shows that, by utilizing a moderate power beam of light, micro‐objects adhered on planar solid substrates can be precisely guided to move in arbitrary directions, realizing sub‐nanometer resolution across extended surfaces. The underlying mechanism is the interplay between surface friction and pulsed opto‐thermo‐elastic deformations, and to render a biased motion with off‐centroid light illumination. This technique enables high‐precision assembly, separation control of nanogaps, regulation of rotation angles in various material‐substrate systems, whose capability is further tested in reconfigurable construction of optoelectronic devices. With simple set‐up and theoretical generality, opto‐thermo‐elastic actuation opens up an avenue for versatile optical manipulation in the solid domain.

Abstract Being able to quantify the phototoxicity of dyes and drugs in live cells allows biologists to better understand cell responses to exogenous stimuli during imaging. This capability further helps to design fluorescent labels with lower phototoxicity and drugs with better efficacy. Conventional ways to evaluate cellular phototoxicity rely on late‐stage measurements of individual or different populations of cells. Here, we developed a quantitative method using intracellular microtubule polymerization as a rapid and sensitive marker to quantify early‐stage phototoxicity. Implementing this method, we assessed the photosensitization induced by organelle dyes illuminated with different excitation wavelengths. Notably, fluorescent markers targeting mitochondria, nuclei, and endoplasmic reticulum exhibited diverse levels of phototoxicity. Furthermore, leveraging a real‐time precision opto‐control technology allowed us to evaluate the synergistic effect of light and dyes on specific organelles. Studies in hypoxia revealed enhanced phototoxicity of Mito‐Tracker Red CMXRos that is not correlated with the generation of reactive oxygen species but a different deleterious pathway in low oxygen conditions.

Abstract Large‐scale particle manipulation with single‐particle precision and further flexible patterning into functional structures is of huge potentials in many fields including bio‐optoelectronic sensing, colloidal lithography, and wearable devices. However, it is very challenging for the precision manipulation and flexible patterning of particles on complicated curved and functional substrates. In this work, opto‐thermal‐tension (OTT) mediated precision large‐scale particle manipulation and flexible patterning based on soap film are reported. Flexible manipulation and subsequent patterning of particles with single‐particle resolution is realized by optothermal regulated surface tension on soap films. Reconfigurable patterning of particle structures with different shapes as well as large‐scale ordered structures (up to 2000 particles) with particle sizes spanning two orders of magnitude (0.5–20 µm) is realized using this OTT mediation method. Importantly, due to the high flexibility of soap films, the patterned large‐scale particle structures can be non‐destructively transferred to curved and rough substrates, including rough iron pipe surface, leaf and skin surface. This OTT mediated method provides a new method for precision large‐scale particle manipulation and flexible patterning with high versatility on complicated functional substrates, with great potentials for optoelectronic and biophotonic sensing and wearable device design on different curved and rough functional substrates.

An optical manipulation method to activate the aggregation‐induced emission (AIE) of Au(I)‐glutathione (Au(I)‐GSH) complexes is presented. First, the well‐known AIE‐type Au(I)‐GSH complexes with a solid emission wavelength of 570 nm are synthesized. At the beginning of the focusing a 1064 nm continuous‐wave (CW) laser at the interface of Au(I)‐GSH complexes solution, its luminescence is hardly detectable. However, with the extension of the laser irradiation time, aggregate appears and rapidly grows, and strong luminescence is shown, indicating the activation of AIE of Au(I)‐GSH complexes through optical manipulation. Surprisingly, the emission peak is at 780 nm and no blue‐shift is observed with the emission intensity increases. The activated AIE emission wavelength by optical manipulation is longer than reported previously, which means that optical manipulation activates AIE in a unique manner. The switching on/off of the activation of AIE is arbitrarily controlled by changing the laser power. In this paper, the luminescence phenomenon and mechanism of AIE are discussed from the perspective of the movement limitation of Au(I)‐GSH complexes under optical manipulation. It is of significant importance for further insights into the luminescence of Au(I)‐GSH complexes and their future development. [ABSTRACT FROM AUTHOR]

Controlling chemical processes in live cells is a challenging task. The spatial heterogeneity of biochemical reactions in cells is often overlooked by conventional means of incubating cells with desired chemicals. A comprehensive understanding of spatially diverse biochemical processes requires precise control over molecular activities at the subcellular level. Herein, a closed‐loop optoelectronic control system is developed that allows the manipulation of biomolecular activities in live cells at high spatiotemporal precision. Chemical‐selective fluorescence signals are utilized to command lasers that trigger specific chemical processes or control the activation of photoswitchable inhibitors at desired targets. This technology is fully compatible with laser scanning confocal fluorescence microscopes. The authors demonstrate selective interactions of a 405 nm laser with targeted organelles and simultaneous monitoring of cell responses by fluorescent protein signals. Notably, blue laser interaction with the endoplasmic reticulum leads to a more pronounced reduction in cytosolic green fluorescent protein signals in comparison to that with nuclei and lipid droplets. Moreover, when combined with a photoswitchable inhibitor, microtubule polymerization is selectively inhibited within the subcellular compartments. This technology enables subcellular spatiotemporal optical manipulation over chemical processes and drug activities, exclusively at desired targets, while minimizing undesired effects on non‐targeted locations. [ABSTRACT FROM AUTHOR]

Whispering gallery mode microlasers are highly sensitive refractive index sensors widely explored for biophotonic and biomedical applications. Microlaser excitation and collection of the emitted light typically utilize microscope objectives at normal incidence, limiting the choice of the oscillation plane of the modes. Here, a platform that enables the excitation of microlasers from various directions using an optically manipulated micromirror is presented. The scheme enables precise sensing of the environment surrounding the microlasers along different well‐controlled planes. The capability of the platform to perform a time‐resolved experiment of dynamic sensing using a polystyrene probe bead orbiting the microlaser is further demonstrated. [ABSTRACT FROM AUTHOR]

Photodiode‐type solar‐blind photodetectors (SBPDs) with the self‐powered feature hold great promise for applications in unattended secure communication, flame detection, and missile warning. However, the responsivity of SBPDs is usually limited due to the severe solar‐blind (SB) light extinction in substrates and charge transport layers. Herein, a spectrally selective hole extraction structure (SHE) is proposed for high‐efficiency perovskite SBPDs. The SHE consisting of a tandem Fabry–Perot cavity and energy‐level‐matched hole transport layer endows the device with narrowband absorption in the SB region and optimized charge extraction capability from the CsPbI2Br perovskite. The optimized SHE exhibits a peak transmittance of 27% at 255 nm and a half maximum at full width of 28 nm. Under SB light illumination, the champion device achieves a responsivity of 56.20 mA W−1 and a detectivity (D*) of 2.86 × 1013 Jones, which are the record values among the reported results. The approach demonstrated here paves the way for the optical and electrical design of perovskite photodetectors with spectrally selective detection. [ABSTRACT FROM AUTHOR]

Metasurface‐based optical field manipulation has significantly broadened the application range of micro‐optical components and integrated optics, gradually replacing bulky and complicated optical components. With the continuous development of micro and nano processing technology as well as computational analysis technology, metasurfaces have progressively shown their superior application prospects. After demonstrating tremendous results in classical optical applications, their application range has now extended to the field of quantum sensing. Due to their unique properties, such as small planar size, easy integration, flexible performance design, and tunable functionality, they have opened up a series of novel and rich applications for generating, manipulating, controlling, and detecting optical fields. In this paper, the basic principle and implementation of quantum measurement are presented and an overview of the design principles of metasurfaces, along with a summary of the latest advancements and potential applications of these surfaces in optical field modulation techniques for quantum precision measurement. Additionally, a thorough discussion and analysis of the challenges encountered by metasurfaces and their future development prospects is provided. Metasurfaces offer brand‐new opportunities for low‐cost, high‐performance, multifunctional miniaturized quantum sensors and are expected to play a significant role in the development of next‐generation quantum sensors. [ABSTRACT FROM AUTHOR]

A method of surfactant-mediated photovoltaic transportation is proposed in this paper, the surfactant (span 80) layers self-assembled at the water-oil and oil-LN interfaces are employed to isolate photovoltaic charges in this method. The reduced electrostatic attenuation, remarkable hydrophobicity, and strong electrical breakdown suppression of the surfactant layers enable the stable and swift transportation of fL-scale aqueous microdroplets using μW-level laser in an oil medium. Three kinds of microdroplet responses to the laser illumination (unresponsive, repulsive and attractive cases) was found. With the increase of surfactant concentration, the driving mechanism can transit from the coulomb repulsion to the dielectrophoretic attraction that facilitates the photovoltaic transportation. Besides, the minimal laser power required for the attractive response was found correlated with the NaCl concentration inside the microdroplet. [ABSTRACT FROM AUTHOR]

Using tight focusing light, optical tweezers (OT) are tools that can manipulate and capture microscopic particles and biological cells as well as characterize a wide range of micro and nanomaterials. In this paper, we focused on fibroblasts, which are widely used in the biomedical area for a variety of purposes, including promoting human wound healing and preventing the early proliferation of tumor cells. We first built an optical tweezer experimental platform, using an 808 nm continuous-wave laser as the capture light source, to confirm that the device can precisely control the movement of single or multiple particles as well as fibroblasts. Then, a 1030 nm femtosecond laser was employed as the capture light source to study the manipulation of microparticles and fibroblasts at different powers. Lastly, a protracted manipulation protocol was used to prevent the fibroblasts from adhering to the wall. This method can be used to isolate and precisely block adherent growth of fibroblasts in cell populations. This experimental result can be further extended to other biological cells. [ABSTRACT FROM AUTHOR]

Perfect vector beams with radius independent of topological charges have garnered significant interest owing to their unique capabilities in optical manipulation, microscopy imaging, and laser micro-machining. However, their polarization state is limited to four modes, restricting their information capacity and re-usability. To address this, we introduce double-ring perfect vectorial vortex beams that leverage the axicon phase to theoretically generate double-ring structures through a Fourier transform. By applying a transformation matrix and introducing a cross phase, we can manipulate the beam distribution. This approach is expected to enhance for development of particle capture and optical communications.

Motors that can convert different forms of energy into mechanical work are of profound importance to the development of human societies. The evolution of micromotors has stimulated many advances in drug delivery and microrobotics for futuristic applications in biomedical engineering and nanotechnology. However, further miniaturization of motors toward the nanoscale is still challenging because of the strong Brownian motion of nanomotors in liquid environments. Here, we develop light-driven opto-thermocapillary nanomotors (OTNM) operated on solid substrates where the interference of Brownian motion is effectively suppressed. Specifically, by optically controlling particle-substrate interactions and thermocapillary actuation, we demonstrate the robust orbital rotation of 80 nm gold nanoparticles around a laser beam on a solid substrate. With on-chip operation capability in an ambient environment, our OTNM can serve as light-driven engines to power functional devices at the nanoscale.

Chiral particles have attracted considerable attention due to their distinctive interactions with light, which enable a variety of cutting-edge applications. This review presents a comprehensive analysis of the optical forces acting on chiral particles, categorizing them into gradient force, radiation pressure, optical lateral force, pulling force, and optical force on coupled chiral particles. We thoroughly overview the fundamental physical mechanisms underlying these forces, supported by theoretical models and experimental evidence. Additionally, we discuss the practical implications of these optical forces, highlighting their potential applications in optical manipulation, particle sorting, chiral sensing, and detection. This review aims to offer a thorough understanding of the intricate interplay between chiral particles and optical forces, laying the groundwork for future advancements in nanotechnology and photonics.

Abstract Controlling chemical processes in live cells is a challenging task. The spatial heterogeneity of biochemical reactions in cells is often overlooked by conventional means of incubating cells with desired chemicals. A comprehensive understanding of spatially diverse biochemical processes requires precise control over molecular activities at the subcellular level. Herein, a closed‐loop optoelectronic control system is developed that allows the manipulation of biomolecular activities in live cells at high spatiotemporal precision. Chemical‐selective fluorescence signals are utilized to command lasers that trigger specific chemical processes or control the activation of photoswitchable inhibitors at desired targets. This technology is fully compatible with laser scanning confocal fluorescence microscopes. The authors demonstrate selective interactions of a 405 nm laser with targeted organelles and simultaneous monitoring of cell responses by fluorescent protein signals. Notably, blue laser interaction with the endoplasmic reticulum leads to a more pronounced reduction in cytosolic green fluorescent protein signals in comparison to that with nuclei and lipid droplets. Moreover, when combined with a photoswitchable inhibitor, microtubule polymerization is selectively inhibited within the subcellular compartments. This technology enables subcellular spatiotemporal optical manipulation over chemical processes and drug activities, exclusively at desired targets, while minimizing undesired effects on non‐targeted locations.

Abstract For centuries, humans have never stopped exploring the nature of light and manipulating it, since light carries multiple information through its intrinsic wave‐particle dualism, including wavelength, amplitude, phase, polarization, spin/orbital angular momentum, etc., which determines the physical language and basic manners we perceive the objective world. Conventional optical devices, such as lenses, prisms, and lasers, are composed of solid elements that are bulky, making it difficult to manipulate light dynamically with multiple degrees‐of‐freedom. Comparatively, some responsive soft matters, especially represented by liquid crystals (LCs), possess distinctive orientational order and spontaneous self‐assembled superstructures, enabling the digital programming of microstructures and multiple degrees‐of‐freedom manipulation of their optical characteristics. The optical manipulation based on these soft superstructures, that is, the “soft‐matter‐photonics”, is playing an impressive role in integrated functional devices, especially in the present age of information explosion. Herein, we review the latest advances, respectively, in the microstructure configurations, multiple degrees‐of‐freedom manipulations, and the relevant prospective applications. Additionally, scientific issues and technical challenges that hinder the programing operation and optical manipulations are discussed. Toward a four‐dimensional optical manipulation of soft condensed matter, this review may have wide implications on a variety of applications, including the integrated fabrication of compact elements, multi‐channel information processing and high‐capacity optical communications.

The active delivery of nanodrugs has been a bottleneck problem in nanomedicine. While modification of nanodrugs with targeting agents can enhance their retention at the lesion location, the transportation of nanodrugs in the circulation system is still a passive process. The navigation of nanodrugs with external forces such as magnetic field has been shown to be effective for active delivery, but the existing techniques are limited to specific materials like magnetic nanoparticles. In this study, an alternative actuation method is proposed based on optical manipulation for remote navigation of nanodrugs in vivo, which is compatible with most of the common drug carriers and exhibits significantly higher manipulation precision. By the programmable scanning of the laser beam, the motion trajectory and velocity of the nanodrugs can be precisely controlled in real time, making it possible for intelligent drug delivery, such as inverse‐flow transportation, selective entry into specific vascular branch, and dynamic circumvention across obstacles. In addition, the controlled mass delivery of nanodrugs can be realized through indirect actuation by the microflow field. The developed optical manipulation method provides a new solution for the active delivery of nanodrugs, with promising potential for the treatment of blood diseases such as leukemia and thrombosis. [ABSTRACT FROM AUTHOR]

Optical manipulation has emerged as a pivotal tool in soft matter research, offering superior applicability, spatiotemporal precision, and manipulation capabilities compared to conventional methods. Here, an overview of the optical mechanisms governing the interaction between light and soft matter materials during manipulation is provided. The distinct characteristics exhibited by various soft matter materials, including liquid crystals, polymers, colloids, amphiphiles, thin liquid films, and biological soft materials are highlighted, and elucidate their fundamental response characteristics to optical manipulation techniques. This knowledge serves as a foundation for designing effective strategies for soft matter manipulation. Moreover, the diverse range of applications and future prospects that arise from the synergistic collaboration between optical manipulation and soft matter materials in emerging fields are explored. [ABSTRACT FROM AUTHOR]

An optimization study is presented to enhance optical dielectrophoretic (ODEP) performance for effective manipulation of an oil-immersed droplet in the floating electrode optoelectronic tweezers (FEOET) device. This study focuses on understanding how the droplet's position and size, relative to light illumination, affect the maximum ODEP force. Numerical simulations identified the characteristic length (Lc) of the electric field as a pivotal factor, representing the location of peak field strength. Utilizing 3D finite element simulations, the ODEP force is calculated through the Maxwell stress tensor by integrating the electric field strength over the droplet's surface and then analyzed as a function of the droplet's position and size normalized to Lc. Our findings reveal that the optimal position is xopt= Lc+ r, (with r being the droplet radius), while the optimal droplet size is ropt = 5Lc, maximizing light-induced field perturbation around the droplet. Experimental validations involving the tracking of droplet dynamics corroborated these findings. Especially, a droplet sized at r = 5Lc demonstrated the greatest optical actuation by performing the longest travel distance of 13.5 mm with its highest moving speed of 6.15 mm/s, when it was initially positioned at x0= Lc+ r = 6Lc from the light's center. These results align well with our simulations, confirming the criticality of both the position (xopt) and size (ropt) for maximizing ODEP force. This study not only provides a deeper understanding of the position- and size-dependent parameters for effective droplet manipulation in FEOET systems, but also advances the development of low-cost, disposable, lab-on-a-chip (LOC) devices for multiplexed biological and biochemical analyses. [ABSTRACT FROM AUTHOR]

The paper briefly presents some essential concepts and features of light fields with strong spatial inhomogeneity of amplitude, phase, polarization, and other parameters. It contains a characterization of optical vortices, speckle fields, polarization singularities. A special attention is paid to the field dynamical characteristics (energy, momentum, angular momentum, and their derivatives), which are considered not only as mechanical attributes of the field but also as its meaningful and application-oriented descriptive parameters. Peculiar features of the light dynamical characteristics in inhomogeneous and dispersive media are discussed. The dynamical properties of paraxial beams and evanescent waves (including surface plasmon -- polaritons) are analyzed in more detail; in particular, a general treatment of the extraordinary spin and momentum, orthogonal to the main propagation direction, is outlined. Applications of structured light fields for optical manipulation, metrology, probing, and data processing are described. [ABSTRACT FROM AUTHOR]

Thermally triggered spatial symmetry breaking in traditional ferroelectrics has been extensively studied for manipulation of the ferroelectricity. However, photoinduced molecular orbital breaking, which is promising for optical control of ferroelectric polarization, has been rarely explored. Herein, for the first time, we synthesized a homochiral fulgide organic ferroelectric crystal (E)‐(R)‐3‐methyl‐3‐cyclohexylidene‐4‐(diphenylmethylene)dihydro‐2,5‐furandione (1), which exhibits both ferroelectricity and photoisomerization. Significantly, 1 shows a photoinduced reversible change in its molecular orbitals from the 3 π molecular orbitals in the open‐ring isomer to 2 π and 1 σ molecular orbitals in the closed‐ring isomer, which enables reversible ferroelectric domain switching by optical manipulation. To our knowledge, this is the first report revealing the manipulation of ferroelectric polarization in homochiral ferroelectric crystal by photoinduced breaking of molecular orbitals. This finding sheds light on the exploration of molecular orbital breaking in ferroelectrics for optical manipulation of ferroelectricity. [ABSTRACT FROM AUTHOR]

Tailoring light–matter interactions in single-layer molybdenum disulfide (MoS2) is vital for its applications in advanced photonic functionalities with tunable optical outputs. Although significant efforts have been devoted to the manipulation of localized photoluminescence (PL) via well-defined plasmonic nanostructures or single shape-controlled nanoantenna, subtle tailoring of optical emission still remains unexplored for wafer-scale production. Here, a tunable PL enhancement of monolayer MoS2 via size-controllable Au nanoparticle (Au NP) arrays is reported. A centimeter-scale Au NP monolayer is prepared by simple annealing of the Au film with different thicknesses, enabling a size-dependent plasmon resonance with a wide range and prominent near-field enhancement. PL emission intensity can be effectively manipulated and enhanced by an elaborate regulation of nanoparticle dimensions. The resonance wavelength and PL enhancement of Au NPs with particular sizes were also in good agreement with the finite-difference time-domain (FDTD) simulations. Tuning the plasmon resonances approximately to a 633 nm excitation light can effectively boost the PL intensity up to 75-fold, which is attributed to the optimally enhanced adsorption of pump laser and the radiative decay rate. A double-layer stacked Au NP structure based on the optimal nanoparticle size is also implemented to realize a further 1.7-fold increase of PL emission derived from the enhanced near-field intensity within the plasmon gaps. The proposed LSPR-tunable plasmonic platform provides flexibility for choosing the operating wavelength of two-dimensional (2D) material-based photonic/optoelectronic devices, as well as a path for a reconfigurable information encoding platform with highly tailorable signal output. [ABSTRACT FROM AUTHOR]

Introducing rotational degree of control into conventional optical tweezers promises unprecedented possibilities in physics, optical manipulation, and life science. However, previous rotational schemes have largely relied upon the intrinsic properties of microsphere anisotropy—such as birefringence or amorphous shape—which involves sophisticated fabrication processes and is limited in their application range. In this study, we demonstrated the first experimental realization of orbiting a homogeneous microsphere by exploiting angular momentum in a transversely rotating optical trap. The high level of rotational control allows us to explore orbital-translational coupling and realize an ultra-stable micro-gyroscope of considerable value. The dynamics of orbital levitated particle was theoretically characterized using a simple model. Our proposed method provided a novel way to qualitatively characterize optical trap features. In the future, the approach could pave the way for investigating rotational opto-mechanics, rotational ground state cooling, and the study of ultra-sensitive angular measurement.

Light can be guided without diffraction in prefabricated structures: optical fibers and waveguides or in actively created spatial solitons in optically nonlinear media. Here, an approach in which a self‐stabilized optical waveguide develops from a reservoir of building blocks—spherical polymer microparticles (MPs)—and is pushed through an optically passive medium—water—is presented. The optical waveguide, formed by a chain of these microparticles and one microsphere wide, is self‐stabilized and propelled by the guided light, while its geometrical and dynamical properties depend on the diameter‐to‐wavelength ratio. The smallest investigated particles, 500 nm in diameter, form single‐mode waveguides up to tens of micrometers long, with the length limited only by optical losses. In contrast, waveguides constructed of larger MPs, 1 and 2.5 µm in diameter, are limited in length to only a few particles due to interference of different modes and beating of light intensity. [ABSTRACT FROM AUTHOR]

The optical nanostructures with high-integration have attracted considerable attentions in the function expansion for the organic light-emitting devices (OLEDs). However, these nanostructures are usually fabricated by hard brittle materials, such as Si, and applied as attached equipment into device system. The traditional integration strategy gradually cannot meet the requirement for ultrathin, high-flexibility and multifunction in the new generation OLEDs. In this work, the electron beam lithography (EBL) has been applied to integrated the optical nanostructures into metallic electrode, realizing the high functional integration into ultrathin OLEDs. After carefully designed the structured electrode, we have successfully integrated the function of charge injection, trapped photons extraction and light collimation into one. And this attempt may provide a feasible strategy for the fabrication of next-generation ultrathin and multifunctional photoelectric devices. [ABSTRACT FROM AUTHOR]

Heating is a knotty factor contributing to device degradation of flexible organic solar cells (FOSCs), and thermal regulation plays a crucial role in the realization of long operational lifetime. Herein, a passive cooling strategy for stable FOSCs is proposed by boosting the optical‐thermal radiative transfer to reduce the insufficient thermal dissipation and the elevated temperature caused by irradiation‐induced heating, while retaining their flexibility and portability. A spectrally selective coupling structure consisting of subwavelength hemisphere pattern and distributed Bragg reflector is integrated into FOSCs to collectively enhance out‐coupling of infrared radiation and limit near‐infrared absorption‐induced heat generation, leading to a reduced heat power intensity of 292.5 W cm−2 and the decreased working temperature by 9.6 °C under outdoor sunlight irradiation. The D18:Y6:PC71BM‐based FOSCs achieve a power conversion efficiency of over 17% with a prolonged T80 lifetime as long as one year under real outdoor working conditions. These results represent a new opportunity for enhancing the operational stability of FOSCs. [ABSTRACT FROM AUTHOR]

A controllable helico-conical beam is proposed in this paper. The intensity patterns and the local spatial frequency of the controllable helico-conical beams in the focal region are analyzed in detail. The results show that the length of the helico-conical beams can be customized by the variable parameter k, and the angular dimension of the bored spiral trajectory is dependent on the proportion k/l. Moreover, the focal-field energy flow density and orbital angular momentum distributions of the controllable helico-conical beams are also analyzed. The proposed helico-conical beams with controllable lengths can be potentially applied in the field of optical guiding. [ABSTRACT FROM AUTHOR]

It is very important for holographic optical tweezers (OTs) to develop high-quality phase holograms through calculation by using some computer algorithms, and one of the most commonly used algorithms is the Gerchberg–Saxton (GS) algorithm. An improved GS algorithm is proposed in the paper to further enhance the capacities of holographic OTs, which can improve the calculation efficiencies compared with the traditional GS algorithm. The basic principle of the improved GS algorithm is first introduced, and then theoretical and experimental results are presented. A holographic OT is built by using a spatial light modulator (SLM), and the desired phase that is calculated by the improved GS algorithm is loaded onto the SLM to obtain expected optical traps. For the same sum of squares due to error SSE and fitting coefficient η, the iterative number from using the improved GS algorithm is smaller than that from using traditional GS algorithm, and the iteration speed is faster about 27%. Multi-particle trapping is first achieved, and dynamic multiple-particle rotation is further demonstrated, in which multiple changing hologram images are obtained continuously through the improved GS algorithm. The manipulation speed is faster than that from using the traditional GS algorithm. The iterative speed can be further improved if the computer capacities are further optimized. [ABSTRACT FROM AUTHOR]

Optical tweezers that rely on laser irradiation to capture and manipulate nanoparticles have provided powerful tools for biological and biochemistry studies. However, the existence of optical diffraction-limit and the thermal damage caused by high laser power hinder the wider application of optical tweezers in the biological field. For the past decade, the emergence of optothermal tweezers has solved the above problems to a certain extent, while the auxiliary agents used in optothermal tweezers still limit their biocompatibility. Here, we report a kind of nanotweezers based on the sign transformation of the thermophoresis coefficient of colloidal particles in low-temperature environment. Using a self-made microfluidic refrigerator to reduce the ambient temperature to around 0 °C in the microfluidic cell, we can control a single nanoparticle at lower laser power without adding additional agent solute in the solution. This novel optical tweezering scheme has provided a new path for the manipulation of inorganic nanoparticles as well as biological particles. [ABSTRACT FROM AUTHOR]

Using tight focusing light, optical tweezers (OT) are tools that can manipulate and capture microscopic particles and biological cells as well as characterize a wide range of micro and nanomaterials. In this paper, we focused on fibroblasts, which are widely used in the biomedical area for a variety of purposes, including promoting human wound healing and preventing the early proliferation of tumor cells. We first built an optical tweezer experimental platform, using an 808 nm continuous-wave laser as the capture light source, to confirm that the device can precisely control the movement of single or multiple particles as well as fibroblasts. Then, a 1030 nm femtosecond laser was employed as the capture light source to study the manipulation of microparticles and fibroblasts at different powers. Lastly, a protracted manipulation protocol was used to prevent the fibroblasts from adhering to the wall. This method can be used to isolate and precisely block adherent growth of fibroblasts in cell populations. This experimental result can be further extended to other biological cells.