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This upload contains the main dataset represented in the figures of the following publication: "Resonators with tailored optical pathby cascaded-mode conversions" by Ginis, Benea-Chelmus et al.

Chemically synthesized metal nanowires are promising building blocks for next-generation photonic integrated circuits, but technological implementation in monolithic integration will be severely hampered by the lack of controllable and precise manipulation approaches, due to the strong adhesion of nanowires to substrates in non-liquid environments. Here, we demonstrate this obstacle can be removed by our proposed earthworm-like peristaltic crawling motion mechanism, based on the synergistic expansion, friction, and contraction in plasmon-driven metal nanowires in non-liquid environments. The evanescently excited surface plasmon greatly enhances the heating effect in metal nanowires, thereby generating surface acoustic waves to drive the nanowires crawling along silica microfibres. Advantages include sub-nanometer positioning accuracy, low actuation power, and self-parallel parking. We further demonstrate on-chip manipulations including transporting, positioning, orientation, and sorting, with on-situ operation, high selectivity, and great versatility. Our work paves the way to realize full co-integration of various functionalized photonic components on single chips., Implementing metal nanowires in photonic circuits is challenging due to lack of suitable manipulation techniques. Here, the authors present an earthworm-like peristaltic crawling motion mechanism, based on surface plasmons and surface acoustic waves, and show on-chip manipulations of single nanowires.

The interface thermal resistance (ITR) of thermal interface materials is discussed in terms of electronic unit heat dissipation. To reduce the ITR of heat-conducting silicone grease (HCSG), low mel...

Optical resonators enable the generation, manipulation, and storage of electromagnetic waves. The physics underlying their operation is determined by the interference of electromagnetic waves, giving rise to the resonance spectrum. This mechanism causes the limitations and trade-offs of resonator design, such as the fixed relationship between free spectral range, modal linewidth, and the resonator's refractive index and size. Here, we introduce a new class of optical resonators, generating resonances by designing the optical path through transverse mode coupling in a cascaded process created by mode-converting mirrors. The generalized round-trip phase condition leads to resonator characteristics that are markedly different from Fabry-Perot resonators and can be tailored over a wide range. We confirm the existence of these modes experimentally in an integrated waveguide cavity with mode converters coupling transverse modes into one supermode. We also demonstrate a transverse mode-independent transmission and show that its engineered spectral properties agree with theoretical predictions., Resonators are key components in optics. In this work, the authors introduce a class of optical resonators with distinctly different properties from conventional resonators, allowing fundamental design trade-offs to be circumvented.

Habitat factors including topography and soil nutrients affect the formation of understory plant diversity patterns on a small spatial scale. Assessing the combination of suitable habitat factors in areas with abundant understory plant diversity is significant for the management and improvement of plant diversity in the plantations. This study used the maximum entropy model (MaxEnt) to simulate the geographical distribution of the area with abundant understory plant diversity and analyzed the contribution of ten habitat factors to the existence probability of the area with abundant understory plant diversity. The results showed that the regions with medium altitude (292–500 m), gentle slope (13–23 degrees), and high soil organic matter content (>2.3 g/kg) were more likely to breed abundant understory plant diversity. Topographic factors had a dominant effect on the spatial distribution of the understory plant diversity, with the importance of 64.9%. Although the effect of soil nutrient factors on understory plant diversity was less than that of topographic factors, it still made up a large proportion (35.1%). Promoting soil biochemical cycles could be an effective way to increase understory plant diversity. By changing soil organic matter content to 2.3 g/kg, soil available nitrogen to 300 mg/kg, and soil available potassium to 120 mg/kg, the average existence probability of the area with abundant understory plant diversity increased from 0.34 to 0.63. We conclude specific measures including introducing the native broad-leaved tree species such as Cotinus coggygria Scop. and Acer truncatum Bunge into the Platycladus orientalis plantation, logging residue management, and litter management are critical for promoting soil biochemical cycles and thereby increasing understory plant diversity.

Canopy interception is an important part of forest ecosystem hydrological processes. It is the first stage of water distribution when rainfall reaches the canopy and has an important impact on nutrient inputs and water exchange. Pinus tabulaeformis is a main tree species in the rocky mountain areas of Northern China, and it is also a primary species for artificial afforestation. In previous studies of canopy interception, applications of the revised Gash model did not take rainfall characteristics into account. Therefore, in this study, rainfall patterns were divided according to the local rainfall characteristics in the rocky mountainous areas of Northern China. Rainfall was divided into three patterns. Rain pattern A was the main rainfall type. Rainfall patterns B and C were two types of rainstorms. Next, the revised Gash model was used to simulate Pinus tabulaeformis plantations under different rainfall patterns. The results showed that the canopy interception rate of Pinus tabulaeformis plantations in this area ranged from 14.7% to 17.9%. The revised Gash model can be used to simulate Pinus tabulaeformis plantations in the rocky mountainous areas of Northern China, with good simulation results for more than 80% of the conventional rainfall patterns. Furthermore, the canopy interception effect of simulated cumulative rainfall events was better than the individual rainfall event. The simulation effect for special rainfall patterns was not good, so it is necessary to improve the model parameters or collect more rainfall samples. These results can be used to explore the applicability of the revised Gash model in Pinus tabulaeformis plantations in the rocky mountain areas of Northern China. They also demonstrate different applicability of the model under different rainfall characteristics.

Synaptic abnormality is an important pathologic feature of autism spectrum disorders (ASDs) and responsible for various behavioral defects in these neurodevelopmental disorders. Microglia are the major immune cells in the brain and also play an important role in synapse refinement. Although dysregulated synaptic pruning by microglia during the brain development has been associated with ASDs, the underlying mechanism has yet to be fully elucidated. Herein, we observed that expression of Transmembrane protein 59 (TMEM59), a protein recently shown to regulate microglial function, was decreased in autistic patients. Furthermore, we found that both male and female mice with either complete or microglia-specific loss of Tmem59 developed ASD-like behaviors. Microglial TMEM59-deficient mice also exhibited enhanced excitatory synaptic transmission, increased dendritic spine density, and elevated levels of excitatory synaptic proteins in synaptosomes. TMEM59-deficient microglia had impaired capacity for synapse engulfment both in vivo and in vitro. Moreover, we demonstrated that TMEM59 interacted with the C1q receptor CD93 and TMEM59 deficiency promoted CD93 protein degradation in microglia. Downregulation of CD93 in microglia also impaired synapse engulfment. These findings identify a crucial role of TMEM59 in modulating microglial function on synapse refinement during brain development and suggest that TMEM59 deficiency may contribute to ASDs through disrupting phagocytosis of excitatory synapse and thus distorting the excitatory-inhibitory (E/I) neuronal activity balance. SIGNIFICANCE STATEMENT Microglia play an important role in synapse refinement. Dysregulated synaptic pruning by microglia during brain development has been associated with autism spectrum disorders (ASDs). However, the underlying mechanism has yet to be fully elucidated. Herein, we observe that the expression of Transmembrane protein 59 (TMEM59), an autophagy-related protein, is decreased in autistic patients. Moreover, we find ASD-like behaviors in mice with complete loss and with microglia-specific loss of Tmem59. Mechanistic studies reveal that TMEM59 deficiency in microglia impairs their synapse engulfment ability likely through destabilizing the C1q receptor CD93, thereby leading to enhanced excitatory neurotransmission and increased dendritic spine density. Our findings demonstrate a crucial role of microglial TMEM59 in early neuronal development and provide new insight into the etiology of ASDs.

We introduce a new class of on-chip optical tweezers with high trapping efficiency, compact footprint, and broadband operation by integrating free-form micro-reflectors and micro-lenses to the facets of waveguides to generate the strong three-dimensional optical field gradient for optical trapping. We demonstrate the design, fabrication, and measurement of both reflective and refractive micro-optical tweezers. The reflective tweezers feature a remarkably small trapping threshold power, and the refractive tweezers are handy for multi-particle trapping and inter-particle interaction analysis. This new class of tweezers is promising for on-chip sensing, cell assembly, particle dynamics analysis, and ion trapping.

We introduce a new class of on-chip optical tweezers with high trapping efficiency, compact footprint, and broadband operation by integrating free-form micro-reflectors to the facets of waveguides.

MXenes have attracted considerable attention for the generation of ultrafast pulsed lasers because of light–matter interactions and excellent saturable absorption characteristics. As a recently developed new member of the MXene family, two-dimensional (2D) molybdenum carbide (Mo2C) exhibits outstanding optical properties. In this study, we synthesized Mo2C nanosheets by using a liquid-phase exfoliation method and studied the nonlinear optical properties of Mo2C nanosheets. The saturation intensity and the modulation depth were measured to be 200 MW cm−2 and 5.1%, respectively. Moreover, we prepared a mode-locker based on a D-shaped fibre Mo2C saturable absorber (SA) by employing evanescent field interactions. By implementing a D-shaped Mo2C SA into ytterbium-doped and erbium-doped fibre lasers, highly stable mode-locked fibre lasers were demonstrated at the 1 micron and 1.5 micron scales, respectively. A pulse duration as short as 290 fs was obtained in the telecommunication window. The corresponding pulse energy and peak power were 0.86 nJ and 2982 W, respectively. Furthermore, a highly stable picosecond-pulse ytterbium-doped fiber laser with a maximum pulse energy of 0.38 nJ was achieved. Compared to recently reported studies based on Mo2C, our experimental results are more advantageous. Our work indicates that a D-shaped Mo2C SA can be used as a broadband mode-locker for potential applications in ultrafast photonics.

Realizing optical manipulation of microscopic objects is crucial in the research fields of life science, condensed matter physics, and physical chemistry. In non-liquid environments, this task is commonly regarded as difficult due to strong adhesive surface force (~µN) attached to solid interfaces that makes tiny optical driven force (~pN) insignificant. Here, by recognizing the microscopic interaction mechanism between friction force—the parallel component of surface force on a contact surface—and thermoelastic waves induced by pulsed optical absorption, we establish a general principle enabling the actuation of micro-objects on dry frictional surfaces based on the opto-thermo-mechanical effects. Theoretically, we predict that nanosecond pulsed optical absorption with mW-scale peak power is sufficient to tame µN-scale friction force. Experimentally, we demonstrate the two-dimensional spiral motion of gold plates on micro-fibers driven by nanosecond laser pulses, and reveal the rules of motion control. Our results pave the way for the future development of micro-scale actuators in non-liquid environments., A general principle enabling the actuation of micro-objects on dry frictional surfaces based on opto-thermo-mechanical effects is established and two-dimensional spiral motions of gold plates on micro-fibers are experimentally demonstrated.

Advances in electron-beam lithography (EBL) have fostered the prominent development of functional micro/nanodevices. Nonetheless, traditional EBL is predominantly applicable to large-area planar substrates and often suffers from chemical contamination and complex processes for handling resists. This paper reports a streamlined and ecofriendly approach to implement e-beam patterning on arbitrary shaped substrates, exemplified by solvent-free nanofabrication on optical fibers. The procedure starts with the vapor deposition of water ice as an electron resist and ends in the sublimation of the ice followed by a "blow-off" process. Without damage and contamination from chemical solvents, delicate nanostructures and quasi-3D structures are easily created. A refractive index sensor is further demonstrated by decorating plasmonic nanodisk arrays on the end face of a single-mode fiber. Our study provides a fresh perspective in EBL-based processing, and more exciting research exceeding the limits of traditional approaches is expected.

The electromagnetic near field enables subwavelength applications such as near-field microscopy and nanoparticle manipulation. Present methods to structure the near field rely on optical antenna theory, involving nanostructures that locally convert propagating waves into confined near-field patterns. We developed a theory of remote rather than local near-field shaping, based on cascaded mode conversion and interference of counterpropagating guided waves with different propagation constants. We demonstrate how to structure at will the longitudinal and transverse variation of the near field, allowing for distributions beyond the conventional monotonic decay of the evanescent field. We provide an experimental realization that confirms our theory. Our method applies to fields with arbitrary polarization states and mode profiles, providing a path toward three-dimensional control of the near field.

The design of the guide sign system is essential to ensure a good interaction mechanism between the user, the space and the sign guidance system, which helps the user complete the spatial positioning and path finding behavior through systematic information transfer. Based on the concept of campus guide sign system, the factors affecting system performance are summarized in the paper. The good strategies of Korean university sign guidance systems are analyzed from function, vision and culture. It is proposed that the college sign guidance system should be designed from the three dimensions of information interaction, visual expression and cultural inheritance considering the relationship between people and campus space, which can become a card to convey the charm of the campus.

To improve the performance of the Radio Frequency Identification (RFID) system and the multi-tag collision problem, a new anti-collision building algorithm is proposed based on the dynamic frame time slot Aloha algorithm and the analysis of binary search and four-slot binary search. In the new algorithm, the reader stack is used to form a further search command; the response tag is divided into four subsets, and the data information is sent in four-time slots, and up to eight tags can be recognized in one search. Simulation results show that the new algorithm greatly reduces the search times and recognition time.

In recent years, cancer has become a major disease endangering human health, lots of data show that about 9.6 [1] million people die of cancer every year. Among them, about 630 [1] thousand people died of Breast cancer..

Electronic switches with nanoscale dimensions satisfy an urgent demand for further device miniaturization. A recent heavily investigated approach for nanoswitches is the use of molecular junctions that employ photochromic molecules that toggle between two distinct isoforms. In contrast to the reports on this approach, we demonstrate that the conductance switch behavior can be realized with only a bare metallic contact without any molecules under light illumination. We demonstrate that the conductance of bare metallic quantum contacts can be reversibly switched over eight orders of magnitude, which substantially exceeds the performance of molecular switches. After the switch process, the gap size between two electrodes can be precisely adjusted with subangstrom accuracy by controlling the light intensity or polarization. Supported by simulations, we reveal a more general and straightforward mechanism for nanoswitching behavior, i.e., atomic switches can be realized by the expansion of nanoelectrodes due to plasmonic heating., Plasmonics: Tripping the light fantastic switch Scientists have shown how light can be used to control a nano-switch, laying the groundwork for atomic-sized devices for use in a range of nanotechnologies. The fabrication of switches with nanoscale dimensions is a fundamental step forward in the further miniaturization of electronic devices, and the realization of fully-integrated nanotechnologies. Now, Dong Xiang and colleagues from Nankai University in China, working with fellow Chinese and international researchers, has developed a method that uses light to control the electrical conductance of the junction between gold nano-electrodes. By heating electrons at the surface of the electrodes with light, a technique known as plasmonic heating, the team was able to expand the electrodes and close the gap between them, turning the switch on. The work could pave the way for new nanotechnologies, including single-molecule transistors and nanopore-based biosensors.

A nanoscale rotary motor driven by optically excited Lamb wave working in air or vacuum is achieved., Achieving light-driven motions in nonliquid environments presents formidable challenges, because microsized objects experience strong dry adhesion and intend to be stuck to contact surfaces with great tenacity. Here, in air and vacuum, we show rotary locomotion of a micrometer-sized metal plate with ~30 nm thickness, revolving around a microfiber. This motor is powered by pulsed light guided into the fiber as a coordinated consequence of an optically excited Lamb wave on the plate and favorable configuration of plate-fiber geometry. The motor, actuated by designed light pulses, crawls stepwise with subnanometer locomotion resolution. Furthermore, we can control the rotation velocity and step resolution by varying the repetition rate and pulse power, respectively. A light-actuated micromirror scanning with 0.001° resolution is then demonstrated on the basis of this motor. It offers unprecedented application potential for integrated micro-opto-electromechanical systems, outer-space all-optical precision mechanics and controls, and laser scanning for miniature lidar systems.

Since its advent in the 1970s, optical tweezers have been widely deployed as a preferred non-contact technique for manipulating microscale objects. On-chip integrated optical tweezers, which afford significant size, weight, and cost benefits, have been implemented, relying upon near-field evanescent waves. As a result, these tweezers are only capable of manipulation in near-surface regions and often demand high power since the evanescent interactions are relatively weak. We introduce on-chip optical tweezers based on freeform micro-optics, which comprise optical reflectors or refractive lenses integrated on waveguide end facets via two-photon polymerization. The freeform optical design offers unprecedented degrees of freedom to design optical fields with strong three-dimensional intensity gradients, useful for trapping and manipulating suspended particles in an integrated chip-scale platform. We demonstrate the design, fabrication, and measurement of both reflective and refractive micro-optical tweezers. The reflective tweezers feature a remarkably low trapping threshold power, and the refractive tweezers are particularly useful for multiparticle trapping and interparticle interaction analysis. Our integrated micro-optical tweezers uniquely combine a compact footprint, broadband operation, high trapping efficiency, and scalable integration with planar photonic circuits. This class of tweezers is promising for on-chip sensing, cell assembly, particle dynamics analysis, and ion trapping.

Based on the analysis of gesture types and gesture recognition technology, this paper divides the function of TV operation interface, designs two sets of gestures based on wearable devices and bare-hand. Using the method of subjective and objective testing, it tests the user fatigue of the two sets of gestures. Finally, experimental results showed that bare-hand gesture interaction technology with its emphasis on natural, comfortable advantage, would become the main way of future home appliance gesture interaction.

Anti-collision algorithm is an important guarantee for Radio Frequency Identification (RFID) system to identify all tags in the reader field, and it is also the key technology to promote the large-scale application of RFID system, the most widely used algorithm is Query Tree (QT). In this paper, a discontinuous collision bit mapping algorithm (DCCMA) is proposed. If collision occurs, the reader sends the custom command to query the collision information, then the tags response the mapping of collision bits to reader. According to the mapping result, the reader generates a more accurate prefix and push it into stack. Compared to the most of existing anti-collision algorithms, simulation results show that our proposed algorithm can achieve better performance in terms of time complexity and communication overload.

A technique to fabricate nanogaps with controllably variable gap width in silver (Ag) nanowires (NWs) by photothermal-induced stress utilizing a focused continuous-wave laser (532 nm) is presented. For the case of an Ag NW on gold thin film, a gap width starting from ∼20 nm is achieved with a critical minimum power (CMP) of about 160 mW, whereas in the case of an Ag NW placed on top of a zinc oxide NW, the attained gap width is as small as a few nm (

Optical force, coming from momentum exchange during light-matter interactions, has been widely utilized to manipulate microscopic objects, though mostly in vacuum or in liquids. By contrast, due to the light-induced thermal effect, photophoretic force provides an alternative and effective way to transport light-absorbing particles in ambient gases. However, in most cases these forces work independently. Here, by employing the synergy of optical force and photophoretic force, we propose and experimentally demonstrate a configuration which can drive a micron-size metallic plate moving back and forth on a tapered fiber with supercontinuum light in ambient air. Optical pulling and oscillation of the metallic plate are experimentally realized. The results might open exhilarating possibilities in applications of optical driving and energy conversion.