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We present an integrated magneto-photonic device for all-optical switching of non-volatile multi-bit spintronic memory. The bits are based on stand-alone magneto-tunnel junctions, which are perpendicularly magnetized with all-optically switchable free layers, coupled onto photonic crystal nanobeam cavities on an indium phosphide based platform. This device enables switching of the magnetization state of the bits by locally increasing the power absorption of light at resonance with the cavity. We design an add/drop network of cavities to grant random access to multiple bits via a wavelength-division multiplexing scheme. Based on a three-dimensional finite-difference time-domain method, we numerically illustrate a compact device capable of switching and accessing at least eight bits in different cavities with a 5 nm wavelength spacing in the conventional (C) telecommunication band. Our multi-bit device holds promise as a new paradigm for developing an ultrafast photonically addressable spintronic memory and may also empower novel opportunities for photonically driven spintronic-based neuromorphic computing. [ABSTRACT FROM AUTHOR]

A colloidal synthesis protocol is demonstrated for InAs@InP core@shell quantum dots (QDs) with a tunable InP shell thickness (ranging from 3 to 8 monolayers), utilizing tris(diethylamino)‐arsine and ‐phosphine. Structural analysis reveals that the InP shell preferentially grows onto the tetrahedral InAs cores along the <‐1‐1‐1> directions, forming tetrapodal‐shaped InAs@InP QDs. Growth of the InP shell causes a red shift in the absorption spectrum of the QDs. This is explained by considering that electrons are delocalized throughout the whole core@shell QDs, while holes preferentially leak along the <‐1‐1‐1> directions, as indicated by the density functional theory calculations. This means such heterostructures cannot be described as type‐I or quasi type‐II, contrary to earlier assumptions. The overlap of carrier wavefunctions throughout the entire InAs@InP QD structure results in no significant reduction of the Auger recombination rate, which remains as fast as in InAs QDs. However, the InP shell enhances photoluminescence (PL) efficiency (up to ≈13%) by passivating surface trap states of the InAs QDs (mainly located close to the top of the valence band). The overgrowth of a ZnSe shell endows the QDs with a high PL efficiency (≈55%) and good stability upon air exposure (≈80% PL intensity retention after 14 days). [ABSTRACT FROM AUTHOR]

Metal-Assisted Chemical Etching (MACE) is a technique for precisely forming nanostructures on semiconductor substrates, and it is actively researched in various fields such as electronic devices, optoelectronic devices, energy storage, and conversion systems. This process offers economic efficiency and effectiveness because it can be performed in a simple chemical laboratory environment without the need for expensive equipment. Particularly, MACE is recognized as an excellent technology for forming various nanostructures due to its advantage of precisely controlling the shape, size, and orientation of nanostructures compared to traditional etching techniques. MACE operates by inducing electrochemical reactions using a metal catalyst, selectively etching the semiconductor surface in a mixed solution of hydrofluoric acid (HF) and hydrogen peroxide ( H 2 O 2 ). The metal catalyst reacts with the oxidant to generate holes, which are injected into the semiconductor substrate to promote oxidation reactions. The oxidized material is then dissolved by HF, progressing the etching process. Precise nanostructures are formed only in the areas with the metal catalyst, and the etching results vary depending on the type, thickness, and deposition method of the catalyst. In this study, we comprehensively review the mechanism of the MACE process, the patterns of nanostructure formation according to the characteristics of catalysts and substrates, and the influence of process variables. We also analyze application cases of MACE in various semiconductor substrates such as silicon (Si), germanium (Ge), indium phosphide (InP), and gallium arsenide (GaAs), and examine the latest research trends and applications utilizing MACE. Nanostructures formed through MACE have the potential to maximize the performance of next-generation semiconductor and optoelectronic devices, and research in this area is expected to greatly contribute to the future development of the semiconductor industry. [ABSTRACT FROM AUTHOR]

Indium phosphide (InP) is emerging as a viable and environmentally friendly alternative to toxic cadmium‐based quantum dots (QDs), especially in the fields of lighting and display. This is owing to similar material properties of InP to those of commercial Cd‐based QDs. Nonetheless, the surface quality of InP needs enhancement through a post‐treatment process to eliminate surface oxides, typically with hydrofluoric acid (HF). The challenge arises with smaller, such as green InP QDs, as HF easily over‐etch the InP cores, thus leading to an unpredictable size distribution and reduced production consistency. This research introduces a refined synthetic strategy that circumvents this over‐etching phenomenon and offers a more precise control over the etching process of smaller InP QDs. By applying an additional protective layer to the InP cores prior to etching and employing ammonium fluoride (NH4F) as an alternative to the conventional HF, the over‐etching incidence can be markedly mitigated. The results reveal that smaller InP/ZnSeS QDs with photoluminescence quantum yield (QY) >90% can be consistently produced, thereby proposing a more efficient and safer method for the fabrication of smaller InP QDs. [ABSTRACT FROM AUTHOR]

The current efficiency records for generating green hydrogen via solar water splitting are held by indium phosphide (InP)‐based photo‐absorbers, protected by TiO2 layers grown through atomic layer deposition (ALD). InP is also a leading material for photonic integrated circuits and computing, where ultrafast near‐surface behavior is key. A previous study described electronic pathways at the phosphorus‐rich (P‐rich) surface of p‐doped InP(100) using time‐resolved two‐photon photoemission (tr‐2PPE) spectroscopy. Here, the intricate electron pathways of the P‐rich InP surface modified with ALD‐deposited TiO2 are explored. Photoexcited bulk InP electrons migrate through a bulk‐to‐surface transition cluster of states and surface states and inject into the TiO2 conduction band (CB). Energy levels and occupation dynamics of CB states in P‐rich InP and TiO2 adlayers are observed, with discrete states preserved up to 10 nm TiO2 deposition. Thermalization lifetimes of excited electrons > 0.8 eV above the InP conduction band minimum (CBM) are preserved for layer thicknesses up to 2.5 nm. Annealing at 300 °C to achieve crystalline TiO2 reconstructions destroys interfacial states, affecting charge transfer. These observations enable innovative engineering of the P‐rich InP/TiO2 heterointerface, opening new possibilities for studying hot‐carrier extraction, adsorbate effects, surface plasmons, and improving photovoltaic and PEC water‐splitting devices. [ABSTRACT FROM AUTHOR]

Manganese-doped colloidal indium phosphide quantum dots with a thin zinc sulfide shell have been synthesized. Nanoclusters were fabricated based on the obtained nanocrystals. The effect of doping of nanocrystals on the process of Förster resonance electronic excitation transfer and the spectral and luminescent properties of nanoclusters was studied for the first time. It has been shown that the luminescence of such clusters radically differs from the luminescence of undoped clusters and depends on the size distribution of nanoparticles included in the nanoclusters. It is shown that the composition of particles participating in Förster transport depends on the time point of observation. [ABSTRACT FROM AUTHOR]

Semiconductors are key to our modern society, enabling a myriad of fields, including electronics, photovoltaics, and photonics. The performance of semiconductor devices can be significantly hampered by defects occurring at the surfaces and interfaces of the semiconductor. As semiconductor devices continue to be scaled and nanostructuring is becoming more commonplace, such defects are increasingly becoming the limiting factor in the device performance. Surface passivation can be used to reduce the number of defects and improve device performance. However, effective surface passivation approaches and requirements can vary greatly depending on the semiconductor material and the envisioned application. In this review, we aim to bring together the separated fields of research on passivation of various semiconductor materials by drawing parallels and highlighting important differences in these fields. To this end, we focus on passivation of silicon, germanium, gallium arsenide, indium phosphide, and gallium nitride. For silicon, a high-quality interface with few defects is relatively straightforward to obtain, and the remaining defects at the surface can be further passivated by hydrogen. For germanium and III–V semiconductors, it is more challenging to form a high-quality interface, and the role of hydrogen for defect passivation is less clear. Nevertheless, similar surface passivation approaches are used for these various semiconductors, and mainly focus on interface management, involving the use of passivation layers combined with surface treatments and/or interlayers. Understanding and extending the toolbox of semiconductor surface passivation will be of great value for effective passivation of current and future semiconductor devices. [ABSTRACT FROM AUTHOR]

Indium phosphide (InP) is widely utilized in the fields of electronics and photovoltaics due to its high electron mobility and high photoelectric conversion efficiency. Strain engineering has been extensively employed in semiconductor devices to adjust physical properties and enhance material performance. In the present work, the band structure and electronic effective mass of InP under different strains are investigated by ab initio calculations. The results show that InP consistently exhibits a direct bandgap under different strains. Both uniaxial strain and biaxial tensile strain exhibit linear effects on the change in bandgap values. However, the bandgap of InP is significantly influenced by uniaxial compressive strain and biaxial tensile strain, respectively. The study of the InP bandgap under different hydrostatic pressures reveals that InP becomes metallic when the pressure is less than −7 GPa. Furthermore, strain also leads to changes in effective mass and the anisotropy of electron mobility. The studies of electronic properties under different strain types are of great significance for broadening the application of InP devices. [ABSTRACT FROM AUTHOR]

Indium phosphide (InP) is an excellent material used in space electronic devices due to its direct band gap, high electron mobility, and high radiation resistance. Displacement damage in InP, such as vacancies, interstitials, and clusters, induced by cosmic particles can lead to the serious degradation of InP devices. In this work, the analytical bond order potential of InP is modified with the short-range repulsive potential, and the hybrid potential is verified for its reliability to simulate the atomic cascade collisions. By using molecular dynamics simulations with the modified potential, the primary damage defects evolution of InP caused by 1–10 keV primary knock-on atoms (PKAs) are studied. The effects of electronic energy loss are also considered in our research. The results show that the addition of electronic stopping loss reduces the number of point defects and weakens the damage regions. The reduction rates of point defects caused by electronic energy loss at the stable state are 32.2% and 27.4% for 10 keV In-PKA and P-PKA, respectively. In addition, the effects of electronic energy loss can lead to an extreme decline in the number of medium clusters, cause large clusters to vanish, and make the small clusters dominant damage products in InP. These findings are helpful to explain the radiation-induced damage mechanism of InP and expand the application of InP devices. [ABSTRACT FROM AUTHOR]

Recent studies on top‐emitting structure, which is designed to enhance the color purity and outcoupling efficiency of quantum‐dot light‐emitting diodes (QLEDs), employ commercially unviable methods owing to limited options for applying the hole injection layer through solution processes on the bottom electrode. In this study, all‐solution‐processable conventional top‐emitting QLEDs (TQLEDs) are successfully fabricated by introducing a polyethylenimine (PEI) interlayer, doping isopropyl alcohol (IPA) into the hole‐injection layer (poly (3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate), PEDOT:PSS), and using the dynamic spin‐coating method. The increased hole injection resulting from the tuned anode‐HIL interface by the PEI and IPA‐doped HIL, coupled with the enhanced outcoupling efficiency and full width at half maximum (FWHM) derived from the optimized cavity length through simulation, realizes a red InP QLED with high efficiency and color purity. The optimized TQLED exhibits a maximum current efficiency and FWHM of 28.04 cd A−1 and 36 nm, respectively, which are threefold higher and 8 nm narrower than those of bottom‐emitting QLEDs, marking the highest current efficiency ever reported for top‐emitting red InP QLEDs. [ABSTRACT FROM AUTHOR]

Air quality is deteriorating due to continuing urbanization and industrialization. In particular, nitrogen dioxide (NO2) is a biologically and environmentally hazardous byproduct from fuel combustion that is ubiquitous in urban life. To address this issue, we report a high‐performance flexible indium phosphide nanomembrane NO2 sensor for real‐time air quality monitoring. An ultralow limit of detection of ~200 ppt and a fast response have been achieved with this device by optimizing the film thickness and doping concentration during indium phosphide epitaxy. By varying the film thickness, a dynamic range of values for NO2 detection from parts per trillion (ppt) to parts per million (ppm) level have also been demonstrated under low bias voltage and at room temperature without additional light activation. Flexibility measurements show an adequately stable response after repeated bending. On‐site testing of the sensor in a residential kitchen shows that NO2 concentration from the gas stove emission could exceed the NO2 Time Weighted Average limit, i.e., 200 ppb, highlighting the significance of real‐time monitoring. Critically, the indium phosphide nanomembrane sensor element cost is estimated at <0.1 US$ due to the miniatured size, nanoscale thickness, and ease of fabrication. With these superior performance characteristics, low cost, and real‐world applicability, our indium phosphide nanomembrane sensors offer a promising solution for a variety of air quality monitoring applications. [ABSTRACT FROM AUTHOR]

Selective area heteroepitaxy provides an alternate solution for the monolithic integration of high-performance III-V lasers on Si with effective management of crystalline defects. Here, we report large-area single-crystal InP grown on (001) patterned silicon-on-insulator (SOI) wafers using the lateral aspect ratio trapping (LART) method by metal-organic chemical vapor deposition. The InP grown on SOI features a length of hundreds of micrometers and a width of up to 8.5 μm with an "in-plane" configuration. Based on fine-tuned growth conditions, especially in the InP nucleation layer on the Si interface, crystalline defects have been minimized resulting in large-area high-quality materials for active devices. Growth mechanisms describing each stage of epitaxy are presented to explain the difference of lateral growth in small and large material volumes. Comprehensive material characterizations and device implementations were performed on the InP/SOI to characterize its viability as an integration platform for photonics. III-V lasers with micro-cavity and Fabry–Perot cavity were fabricated and statistically analyzed to demonstrate the feasibility of providing photonic function. Attaining large-area InP/SOI addresses the bottleneck of limited III-V material volume in selective epitaxy leading to a critical step toward monolithic integration of III-V on Si. Furthermore, the high-quality InP/SOI could serve as a mini template for regrowth to construct various photonic building blocks. Large-area and high-quality III-V on SOI here ensure LART as an easy, flexible, and tolerable method for the potential realization of fully integrated Si photonics. [ABSTRACT FROM AUTHOR]

The paper demonstrates the possibility of forming specific nanostructures of the "parquet" type of nanowires on the InP surface. The resulting nanostructure is characterised by an ordered transverse and longitudinal relative shift of separate nanowires. A dislocation model is proposed that explains the mechanism of such structure formation. The numerical estimates of the geometric parameters of the nanostructure obtained during theoretical modelling are quite adequate for the experimental results. [ABSTRACT FROM AUTHOR]

The optical properties of non-toxic indium phosphide (InP) quantum dots (QDs) are impinged by the existence of characteristic deep trap states. Several surface engineering strategies have been adopted to improve their optical quality, which has promoted the use of InP QDs for various technological applications. An antithetical approach involves the effective utilization of the deep trap states in InP QDs to modulate back electron transfer rates. Here, we explore the influence of the core-size of InP on their In-to-P stoichiometry and charge transfer dynamics when bound to an acceptor molecule, decyl viologen (DV2+). The mechanism of interaction of InP and DV2+ based on the quenching sphere model established the presence of (i) a 1:1 complex of DV2+ bound on InP and (ii) immobile quenchers in the quenching sphere, depending on the concentration of DV2+. While the forward electron transfer rates from photoexcited InP to bound DV2+ does not substantially vary with an increase in core size, the back electron transfer rates are found to be retarded. Findings from inductively coupled plasma-optical emission spectroscopy (ICP-OES) and X-ray photoelectron spectroscopy (XPS) reveal that the In to P ratio is higher for QDs with larger core size, which further brings about increased carrier trapping and a decreased rate of charge recombination. Furthermore, long-lived charge-separated states in DV2+ bound to InP, extending to hundreds of milliseconds, are obtained by varying the number of DV2+ in the quenching sphere of the QDs. [ABSTRACT FROM AUTHOR]

Through the experiments of indium phosphide (InP) crystal growth, it was found that InP crystals with twin-free or low twinning probability can be grown repeatedly in the range of 0-90° growth angles at a high temperature gradient and low growth rate. Based on the experimental phenomena, it is inferred that twin formation is mainly related to undercooling at the growth interface. A kinetic model for twin nucleation based on the morphologies of the triple junction (tri-junction) region has been proposed from the point of view of the nucleation kinetics of crystal growth. It is found that when the undercooling of facets exceeds a critical value, the probability of twin nucleation increases with the increase of undercooling. When the twin boundary energy is 0.5 mJ m-2, this critical value approaches 0.2 K. Based on this model, the comprehensive influence of interface morphologies, temperature gradients, and growth rates on twin nucleation was analyzed. In addition, the effects of temperature fluctuations, constitutional supercooling, impurities and dopants have also been well explained. By controlling the morphologies of the growth interface under low undercooling, InP single crystals with a diameter of 170 mm were prepared using a flat shoulder method. [ABSTRACT FROM AUTHOR]

We present the design, fabrication, and characterization results of a compact, widely tunable laser realized on an indium phosphide membrane-on-silicon (IMOS) platform. The laser features a compact Mach–Zehnder interferometric structure as the wavelength-selective intracavity filter with a footprint of 0.13 mm2. The filter design is optimized to ensure narrow filter transmission and high side-mode-to-main-mode-ratio, enabling single-mode operation for the laser. The high optical confinement on the IMOS platform can support tight waveguide bends. Leveraging this, the laser achieves a short cavity length, further enhancing the single-mode operation. Measurement results indicate a threshold current of 29 mA and a maximum on-chip output power of approximately 3.6 dBm and wall plug efficiency of 1.8%. The side-mode suppression ratio ranges from 30 to 44 dB, with a tuning range spanning 40 nm, from 1555 to 1595 nm. A complete tuning lookup table is generated via an automated setup incorporating a stochastic search algorithm. [ABSTRACT FROM AUTHOR]

The fundamental properties of indium phosphide (InP) doped with tellurium and, subsequently, compensated with copper are considered. Data are presented on the existence of four qualitative patterns of the empirical photoconductivity (PC) spectra of InP:Cu in its own region. Works with semiempirical approximation of the PC of sensitive InP:Cu samples are indicated. It is noted that the PC of IP(α()) was analytically approximated as a function of the experimentally obtained spectral dependence of the absorption coefficient of InP. Five approximating functions are proposed in order to obtain an analytical dependence of the absorption coefficient of InP α(). Five dependencies with different values of the standard deviation are obtained. Based on the analytical dependencies, the complete analytical dependence of IP(α()) is modeled. Similarly, five dependencies are obtained, characterized by the corresponding value of the standard deviation. Five nonstationary PC surfaces of IP (as a function of two variables: absorption coefficient, as a function of photon energy, and sample exposure time under normal conditions) are constructed. A conclusion is made about the choice of the most mathematically accurate and physically meaningful approximating function α(). Accordingly, it is shown that this dependence is optimal for obtaining based on it (including this dependence in the structure of IP = f(α) and α = f()) a complete analytical description of the PC process. It is shown that subsequent studies can be aimed at explaining the physical bases of PC in the short-wave region of the fundamental transitions of InP and studying methods of influencing the surface layer of InP:Cu, with the aim of sensitizing and stabilizing it. [ABSTRACT FROM AUTHOR]

In this study, we focus on the development of key processes towards wafer-scale 3-dimentional/vertical (3D) integration of Indium-Phosphide (InP) photonic membranes on InP electronics via adhesive bonding. First, we identified the most critical steps and optimized them to achieve high thermal and mechanical compatibility of components for the co-integration process. Next, we developed a strategy for InP-to-InP wafer bonding with high topology tolerance, and introduced hard benzocyclobutene (BCB) anchors to preserve the alignment and BCB thickness uniformity after bonding. The resulting bond layer is homogeneous in terms of physical and mechanical properties. Finally, we developed a novel method to selectively remove the InP substrate from the photonics side via wet etching while protecting the electronics carrier wafer with hermetic multi-layer coatings. The investigation of these key steps is essential for scalable 3D integration of photonics and electronics at ultra short distances (< $15 ~\mu \text{m}$). [ABSTRACT FROM AUTHOR]

High‐power optical transmission (HPOT) technology has emerged as a promising alternative among far‐field wireless power transmission approaches, enabling the transfer of kilowatts of power over kilometer‐scale distances. Its exceptional adaptability allows operation in challenging scenarios where traditional electrical wiring is impractical or unfeasible, thereby opening up a vast array of potential applications previously considered utopian. An important pending assignment in enhancing the performance of laser‐based HPOT systems is achieving efficient photovoltaic conversion of high power densities (≥10 W cm−2). In this sense, there is a pressing need for the advancement of optical photovoltaic converters (OPCs) capable of enduring intense monochromatic irradiances. This work presents the design optimization, manufacturing, and characterization processes of a gallium indium phosphide (GaInP)‐based OPC under varying 637 nm laser power at room temperature. In addition, methods to evaluate the impact of temperature on performance are provided. The findings reveal a maximum efficiency of 53.5% at 10 W cm−2, surpassing literature results for GaInP converters by over 9%abs at those light intensities. Remarkably, this device withstands unmatched irradiances within GaInP OPCs up to 60 W cm−2, maintaining 42.3% efficiency. This study aims to push forward the development of wide‐bandgap power converters with recordbreaking efficiencies paving the way for new applications. [ABSTRACT FROM AUTHOR]

Next‐generation "Beyond 5G (B5G)/6G" wireless network systems have been researched and developed for meeting the rapid growth of mobile traffic. A high‐yield fabrication process of InP‐based transistors and tera‐hertz monolithic integrated circuits with 300 GHz operation is reported, which is a candidate frequency for "Beyond 5G/6G" network systems. The main focus is on a high‐yield and reproductive fabrication process of InP‐based high electron mobility transistors (HEMTs) while revisiting previous studies. The DC and radio frequency characteristics of fabricated InP‐HEMTs from the viewpoint of integrating circuits are described. Then, high‐frequency performances of ft = 280 GHz and fmax = 860 GHz in the bias conditions of Vgs/Vds = 0.2/1.1 V with good uniformity are obtained. Finally, InP‐based 300 GHz‐band mixer and power amplifiers are introduced, to which a backside process is also applied for ensuring their stability and enhancing output power. [ABSTRACT FROM AUTHOR]

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Environment-friendly indium phosphide (InP)-based quantum dots (QDs) with efficient red-emitting properties are sufficiently needed to satisfy the requirement of burgeoning display and lighting technology. Currently, the syntheses of InP QDs using tris(trimethylsilyl)phosphine as the precursor are highly toxic and expensive. Herein, we successfully introduced gallium (Ga) ions into tris(dimethylamino)phosphine-based red InP cores through thermally-promoted cation exchange, and the obtained Ga-doped InP cores exhibited significantly increased photoluminescence quantum yields (PLQY) of up to 26%. The existence of Ga was directly confirmed by energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy, and the functions of Ga were systematically studied. After subsequent coating of Ga-doped InP cores with ZnSeS and ZnS shells, the resulting Ga-InP/ZnSeS/ZnS QDs achieved a high PLQY of 62% with an emission maximum at 640 nm. In contrast, without Ga-doping, the PLQY only attained 36% using the same synthetic approach. This indicated an approximate 1.7-fold increase in PLQY. The enhancement of photoluminescence was related to the Ga3+, as it not only passivated surface defects of InP cores but also reduced core-shell interface stress. The Ga-InP/ZnSeS/ZnS QDs exhibited good stability towards heat treatment and ultraviolet (UV) irradiation. Moreover, the red light-emitting diode (LED) based on Ga-InP/ZnSeS/ZnS QDs performed well in a wide injected current range of 2 to 200 mA, with a maximum power efficiency of 0.68 lm/W. This work showcases Ga-doping through cation exchange as a promising strategy for enhancing the efficiency of InP-based red emitters. [ABSTRACT FROM AUTHOR]

An erratum has been published regarding a previous article on the structure formation on the surface of indium phosphide irradiated by femtosecond laser pulses. The erratum identifies typographical errors in three equations related to calculating the efficacy factor. The corrected equations are provided, and it is noted that the computer algebra code used in the original article was not affected by these errors. The erratum also includes implementations of the corrected equations in Mathematica and Python, as well as acknowledgments and data availability information. [Extracted from the article]

Abstract Recent studies on top‐emitting structure, which is designed to enhance the color purity and outcoupling efficiency of quantum‐dot light‐emitting diodes (QLEDs), employ commercially unviable methods owing to limited options for applying the hole injection layer through solution processes on the bottom electrode. In this study, all‐solution‐processable conventional top‐emitting QLEDs (TQLEDs) are successfully fabricated by introducing a polyethylenimine (PEI) interlayer, doping isopropyl alcohol (IPA) into the hole‐injection layer (poly (3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate), PEDOT:PSS), and using the dynamic spin‐coating method. The increased hole injection resulting from the tuned anode‐HIL interface by the PEI and IPA‐doped HIL, coupled with the enhanced outcoupling efficiency and full width at half maximum (FWHM) derived from the optimized cavity length through simulation, realizes a red InP QLED with high efficiency and color purity. The optimized TQLED exhibits a maximum current efficiency and FWHM of 28.04 cd A−1 and 36 nm, respectively, which are threefold higher and 8 nm narrower than those of bottom‐emitting QLEDs, marking the highest current efficiency ever reported for top‐emitting red InP QLEDs.

Abstract Indium phosphide (InP) is a binary semiconductor composed of indium and phosphorus. It has a zinc blende crystal structure, which is a type of cubic lattice structure. This lattice is composed of indium and phosphorus atoms arranged in a lattice of cube-shaped cells, with each cell containing four indium atoms and four phosphorus atoms. This lattice structure is the same for all materials with a zinc blende crystal structure and is the most common type of lattice structure in semiconductors. Indium phosphide (InP) has several chemical applications. It is commonly used as a dopant in the production of semiconductors, where it helps control the electrical properties of the material. InP is also utilized in the synthesis various indium-containing compounds, which can have applications in catalysts and chemical reactions. Additionally, InP nanoparticles have been investigated for their potential use in biomedical imaging and drug delivery systems. The topological characterization of 3D molecular structures can be performed via graph theory. In graph theory, the connections between atoms are represented as edges and the atoms themselves are represented as nodes. Furthermore, graph theory can be used to calculate the topological descriptors of the molecule such as the degree-based and reverse degree-based irregularity toplogical indices. These descriptors can be used to compare the topology of different molecules. This paper deals with the modeling and topological characterization of indium phosphide $$({\text{InP}})$$ ( InP ) via degree-based and reverse irregularity indices. The 3D crystal structure of the InP is topologically modeled via partition of the edges, and derived closed form expressions for its irregularity indices. Our obtained results will be surely be helpful in investigating the QSPR/QSAR analysis as well as understanding the deep irregular behavior of the indium phosphide $$({\text{InP}})$$ ( InP ) .

Abstract We present an integrated optical phased array (OPA) which embeds in-line optical amplifiers and phase modulators to provide beam-forming capability with gain and beam steering in the 1465–1590 nm wavelength range. We demonstrate up to 21.5 dB net on-chip gain and up to 35.5 mW optical output power. The OPA circuit is based on an InP photonic integration platform and features the highest measured on-chip gain and output power level recorded in an active OPA (i.e., with amplification), to the best of our knowledge. Furthermore, the OPA enables the independent control of both amplitude and phase in its arms and through this we demonstrate programmable beam shaping for two cases. First, we carried out a Gaussian apodization of the power distribution profile in the OPA emitter waveguides, leading to 19.8 dB sidelobe suppression in the far-field beam, which is the highest value recorded for active OPAs, and then we demonstrated beam forming of 0th, 1st, and 2nd order 1D Hermite–Gaussian beams in free-space.

This work highlights the novel approach of incorporating potassium iodide (KI) doping during the synthesis of In0.53P0.47 core quantum dots (QDs) to significantly reduce the concentration of vacancies (i.e., In vacancies; VIn−) within the bulk of the core QD and inhibit the formation of InPOx at the core QD–Zn0.6Se0.4 shell interfaces. The photoluminescence quantum yield (PLQY) of ~97% and full width at half maximum (FWHM) of ~40 nm were achieved for In0.53P0.47/Zn0.6Se0.4/Zn0.6Se0.1S0.3/Zn0.5S0.5 core/multi-shell QDs emitting red light, which is essential for a quantum-dot organic light-emitting diode (QD-OLED) without red, green, and blue crosstalk. KI doping eliminated VIn− in the core QD bulk by forming K+-VIn− substitutes and effectively inhibited the formation of InPO4(H2O)2 at the core QD–Zn0.6Se0.4 shell interface through the passivation of phosphorus (P)-dangling bonds by P-I bonds. The elimination of vacancies in the core QD bulk was evidenced by the decreased relative intensity of non-radiative unpaired electrons, measured by electron spin resonance (ESR). Additionally, the inhibition of InPO4(H2O)2 formation at the core QD and shell interface was confirmed by the absence of the {210} X-ray diffraction (XRD) peak intensity for the core/multi-shell QDs. By finely tuning the doping concentration, the optimal level was achieved, ensuring maximum K-VIn− substitution, minimal K+ and I− interstitials, and maximum P-dangling bond passivation. This resulted in the smallest core QD diameter distribution and maximized optical properties. Consequently, the maximum PLQY (~97%) and minimum FWHM (~40 nm) were observed at 3% KI doping. Furthermore, the color gamut of a QD-OLED display using R-, G-, and B-QD functional color filters (i.e., ~131.1%@NTSC and ~98.2@Rec.2020) provided a nearly perfect color representation, where red-light-emitting KI-doped QDs were applied. [ABSTRACT FROM AUTHOR]

Optical frequency combs (OFCs) have evolved into one of the most active areas of photonics, underpinning advancements in both fundamental science and commercial contexts. Electro‐optic modulation for OFC generation offers excellent versatility, stability, and phase coherence. With the rapid progress in micro‐nano fabrication techniques, electro‐optic frequency combs (EOFCs) have been realized on many integrated platforms, including silicon on insulator (SOI), indium phosphide (InP), and lithium niobate on insulator (LNOI). These compact, low‐cost, and energy‐efficient EOFCs support a wide range of applications. In this study, we review the theory for the generation of integrated EOFCs, summarize the demonstrations on the main integrated platforms, present applications, and envision the development directions of integrated EOFCs in view of materials, devices, and applications. [ABSTRACT FROM AUTHOR]

Light-harvesting studies in donor–acceptor nanohybrid systems based on all-environmentally friendly quantum dots (QDs) are necessary to realize their applications in energy and medical research. Here, we demonstrate an efficient Förster resonance energy transfer (FRET) process in an electrostatically bound all-QD based assembly comprised of indium phosphide/zinc sulfide (InP/ZnS) QDs as both the donor and the acceptor. A perfect control on the speed of nucleation and growth steps, along with appropriate surface functionalization with oppositely charged ligands, enabled an electrostatically bound all-QD donor–acceptor nanohybrid assembly comprising of green- and red-emitting InP/ZnS QDs. Detailed spectroscopic studies revealed the importance of electrostatic attraction in accomplishing an efficient FRET process (∼75%) from donor [+] G-InP/ZnS QDs to acceptor [−] R-InP/ZnS QDs. Further, solid-state studies helped in visualizing the distance-dependent nature of the FRET process at a fixed donor–acceptor ratio. The all-InP QD containing donor–acceptor nanohybrid assembly developed here could find applications in other light-harvesting studies as well, including photovoltaics and photocatalysis. [ABSTRACT FROM AUTHOR]

Indium phosphide (InP) is a binary semiconductor composed of indium and phosphorus. It has a zinc blende crystal structure, which is a type of cubic lattice structure. This lattice is composed of indium and phosphorus atoms arranged in a lattice of cube-shaped cells, with each cell containing four indium atoms and four phosphorus atoms. This lattice structure is the same for all materials with a zinc blende crystal structure and is the most common type of lattice structure in semiconductors. Indium phosphide (InP) has several chemical applications. It is commonly used as a dopant in the production of semiconductors, where it helps control the electrical properties of the material. InP is also utilized in the synthesis various indium-containing compounds, which can have applications in catalysts and chemical reactions. Additionally, InP nanoparticles have been investigated for their potential use in biomedical imaging and drug delivery systems. The topological characterization of 3D molecular structures can be performed via graph theory. In graph theory, the connections between atoms are represented as edges and the atoms themselves are represented as nodes. Furthermore, graph theory can be used to calculate the topological descriptors of the molecule such as the degree-based and reverse degree-based irregularity toplogical indices. These descriptors can be used to compare the topology of different molecules. This paper deals with the modeling and topological characterization of indium phosphide (InP) via degree-based and reverse irregularity indices. The 3D crystal structure of the InP is topologically modeled via partition of the edges, and derived closed form expressions for its irregularity indices. Our obtained results will be surely be helpful in investigating the QSPR/QSAR analysis as well as understanding the deep irregular behavior of the indium phosphide (InP) . [ABSTRACT FROM AUTHOR]

Electro-optic modulators (EOMs) are pivotal in bridging electrical and optical domains, essential for diverse applications including optical communication, microwave signal processing, sensing, and quantum technologies. However, achieving the trifecta of high-density integration, cost-effectiveness, and superior performance remains challenging within established integrated photonics platforms. Enter thin-film lithium niobate (LN), a recent standout with its inherent electro-optic (EO) efficiency, proven industrial performance, durability, and rapid fabrication advancements. This platform inherits material advantages from traditional bulk LN devices while offering a reduced footprint, wider bandwidths, and lower power requirements. Despite its recent introduction, commercial thin-film LN wafers already rival or surpass established alternatives like silicon and indium phosphide, benefitting from decades of research. In this review, we delve into the foundational principles and technical innovations driving state-of-the-art LN modulator demonstrations, exploring various methodologies, their strengths, and challenges. Furthermore, we outline pathways for further enhancing LN modulators and anticipate exciting prospects for larger-scale LN EO circuits beyond singular components. By elucidating the current landscape and future directions, we highlight the transformative potential of thin-film LN technology in advancing electro-optic modulation and integrated photonics. [ABSTRACT FROM AUTHOR]

The degradation properties of Indium phosphide hetero-junction bipolar transistors (InP HBTs) under proton irradiation are studied and modelled using a compact model for pre-irradiation, post-irradiation, and post-annealing. The variation rates of the model parameters, such as the base–emitter saturation current (ISE) and ideality factor in the ideal region (NE) in the forward Gummel characteristics, the zero-biased capacitance (Cje) and the grading factor (Mjer) in the BE junction capacitance, and the transit time parameter in the base region (Tfb), are analysed to delve into the degradation mechanism induced by proton irradiation. The displacement damage, induced by proton irradiation in the space charge region of the base–emitter junction and in the quasi-neutral bulk base region, is found to be responsible for the decrease in current gain and cut-off frequency. After annealing, the variation rates of the parameters decrease significantly compared to post-irradiation. This suggests that the recombination of unstable defects leads to a slight recovery in the degradation characteristics of InP HBTs after a period of annealing. [ABSTRACT FROM AUTHOR]

The number of photonic components integrated into the same circuit is approaching one million, but so far, this has been without the large-scale integration of active components: lasers, amplifiers, and high-speed modulators. Emerging applications in communication, sensing, and computing sectors will benefit from the functionality gained with high-density active–passive integration. Indium phosphide offers the richest possible combinations of active components, but in the past decade, their pace of integration scaling has not kept up with passive components realized in silicon. In this work, we offer a perspective for functional scaling of photonic integrated circuits with actives and passives on InP platforms, in the axes of component miniaturization, areal optimization, and wafer size scaling. [ABSTRACT FROM AUTHOR]

We present an integrated optical phased array (OPA) which embeds in-line optical amplifiers and phase modulators to provide beam-forming capability with gain and beam steering in the 1465–1590 nm wavelength range. We demonstrate up to 21.5 dB net on-chip gain and up to 35.5 mW optical output power. The OPA circuit is based on an InP photonic integration platform and features the highest measured on-chip gain and output power level recorded in an active OPA (i.e., with amplification), to the best of our knowledge. Furthermore, the OPA enables the independent control of both amplitude and phase in its arms and through this we demonstrate programmable beam shaping for two cases. First, we carried out a Gaussian apodization of the power distribution profile in the OPA emitter waveguides, leading to 19.8 dB sidelobe suppression in the far-field beam, which is the highest value recorded for active OPAs, and then we demonstrated beam forming of 0th, 1st, and 2nd order 1D Hermite–Gaussian beams in free-space. [ABSTRACT FROM AUTHOR]

We report an in-situ construction strategy of Z-type In 2 O 3 @InP hydrogen evolution reaction (HER) electrocatalyst with well-defined core-shell structure on nickel foam (In 2 O 3 @InP/NF) via sequential hydrothermal, annealing, and phosphating steps. The phosphating time dramatically affects the morphology, crystal phase, elemental composition, and optical properties of In 2 O 3 @InP. The resulting electrode obtained with 2 h of phosphating time has smaller overpotentials and Tafel slope, larger TOF and ECSA, and lower charge transfer resistance compared to In 2 O 3 /NF. The better activity reveals the promoted roles of InP that can provide more active sites, facilitate charge transfer, and accelerate the adsorption of H* species. The photo-assisted electrocatalytic activity for HER is significantly enhanced attributed to the strong light absorption capacity of InP, superior energy level configuration of In 2 O 3 and InP, and excellent transient light response of In 2 O 3 @InP. Furthermore, the electrode has favorable stability and durability, and the morphology and surface chemical state have no essential changes after the photo-assisted HER stability test. The promoting mechanism of photo-assisted HER for the Z-type In 2 O 3 @InP/NF electrode and HER activities in the dark and under AM 1.5 G light illumination. [Display omitted] • The in-situ construction strategy of In 2 O 3 @InP core-shell heterostructure is used. • The InP layer enhances surface chemical states and optical properties of In 2 O 3. • In 2 O 3 @InP has superior photo-assisted activity, stability, and durability for HER. • The promoting mechanism of photo-assisted HER for Z-type In 2 O 3 @InP is determined. [ABSTRACT FROM AUTHOR]

Airplane produced contrail cirrus has a greenhouse effect in our atmosphere. It has an effect that is as much as or more than any other airplane emission such as airplane produced CO2 Karcher et al. 2018. With air traffic anticipated to increase into the future it is important to understand contrail cirrus formation. We present a new receiver instrument using the 424 GHz (O2) and 448 GHz (H2O) emission lines for thermal and humidity profiling that will provide data to model airplane contrail formation. Such an instrument can be used for guiding aircraft flight paths to reduce the development of contrail cirrus that can have an immediate greenhouse effect in our atmosphere.

Density-functional theory calculations on P-rich InP(001):H surfaces are presented. Depending on temperature, pressure and substrate doping, hydrogen desorption or adsorption will occur and influence the surface electronic properties. For p-doped samples, the charge transition levels of the P dangling bond defects resulting from H desorption will lead to Fermi level pinning in the lower half of the band gap. This explains recent experimental data. For n-doped substrates, H-deficient surfaces are the ground-state structure. This will lead to Fermi level pinning below the bulk conduction band minimum. Surface defects resulting from the adsorption of additional hydrogen can be expected as well, but affect the surface electronic properties less than H desorption.

Indium phosphide (InP) is an excellent material used in space electronic devices due to its direct band gap, high electron mobility, and high radiation resistance. Displacement damage in InP, such as vacancies, interstitials, and clusters, induced by cosmic particles can lead to the serious degradation of InP devices. In this work, the analytical bond order potential of InP is modified with the short-range repulsive potential, and the hybrid potential is verified for its reliability to simulate the atomic cascade collisions. By using molecular dynamics simulations with the modified potential, the primary damage defects evolution of InP caused by 1–10 keV primary knock-on atoms (PKAs) are studied. The effects of electronic energy loss are also considered in our research. The results show that the addition of electronic stopping loss reduces the number of point defects and weakens the damage regions. The reduction rates of point defects caused by electronic energy loss at the stable state are 32.2% and 27.4% for 10 keV In-PKA and P-PKA, respectively. In addition, the effects of electronic energy loss can lead to an extreme decline in the number of medium clusters, cause large clusters to vanish, and make the small clusters dominant damage products in InP. These findings are helpful to explain the radiation-induced damage mechanism of InP and expand the application of InP devices.

Indium phosphide (InP) is widely utilized in the fields of electronics and photovoltaics due to its high electron mobility and high photoelectric conversion efficiency. Strain engineering has been extensively employed in semiconductor devices to adjust physical properties and enhance material performance. In the present work, the band structure and electronic effective mass of InP under different strains are investigated by ab initio calculations. The results show that InP consistently exhibits a direct bandgap under different strains. Both uniaxial strain and biaxial tensile strain exhibit linear effects on the change in bandgap values. However, the bandgap of InP is significantly influenced by uniaxial compressive strain and biaxial tensile strain, respectively. The study of the InP bandgap under different hydrostatic pressures reveals that InP becomes metallic when the pressure is less than −7 GPa. Furthermore, strain also leads to changes in effective mass and the anisotropy of electron mobility. The studies of electronic properties under different strain types are of great significance for broadening the application of InP devices.

In recent years, the growing concern over the presence of toxic aquatic pollutants has prompted intensive research into effective and environmentally friendly remediation methods. Photocatalysis using semiconductor quantum dots (QDs) has developed as a promising technology for pollutant degradation. Among various QD materials, indium phosphide (InP) and its hybrid with zinc sulfide (ZnS) have gained considerable attention due to their unique optical and photocatalytic properties. Herein, InP and InP/ZnS QDs were employed for the removal of dyes (crystal violet, and congo red), polyaromatic hydrocarbons (pyrene, naphthalene, and phenanthrene), and pesticides (deltamethrin) in the presence of visible light. The degradation efficiencies of crystal violet (CV) and congo red (CR) were 74.54% and 88.12% with InP, and 84.53% and 91.78% with InP/ZnS, respectively, within 50 min of reaction. The InP/ZnS showed efficient performance for the removal of polyaromatic hydrocarbons (PAHs). For example, the removal percentage for naphthalene, phenanthrene, and pyrene was 99.8%, 99.6%, and 88.97% after the photocatalytic reaction. However, the removal percentage of InP/ZnS for pesticide deltamethrin was 90.2% after 90 min light irradiation. Additionally, advanced characterization techniques including UV–visible spectrophotometer (UV–Vis), photoluminescence (PL), X-ray diffractometer (XRD), energy-dispersive spectrometer (EDS) elemental mapping, transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) were used to analyze the crystal structure, morphology, and purity of the fabricated materials in detail. The particle size results obtained from TEM are in the range of 2.28–4.60 nm. Both materials (InP and InP/ZnS) exhibited a spherical morphology, displaying distinct lattice fringes. XRD results of InP depicted lattice planes (111), (220), and (311) in good agreement with cubic geometry. Furthermore, the addition of dopants was discovered to enhance the thermal stability of the fabricated material. In addition, QDs exhibited efficacy in the breakdown of PAHs. The analysis of their fragmentation suggests that the primary mechanism for PAHs degradation is the phthalic acid pathway. [ABSTRACT FROM AUTHOR]

Density-functional theory calculations on P-rich InP(001):H surfaces are presented. Depending on temperature, pressure and substrate doping, hydrogen desorption or adsorption will occur and influence the surface electronic properties. For p-doped samples, the charge transition levels of the P dangling bond defects resulting from H desorption will lead to Fermi level pinning in the lower half of the band gap. This explains recent experimental data. For n-doped substrates, H-deficient surfaces are the ground-state structure. This will lead to Fermi level pinning below the bulk conduction band minimum. Surface defects resulting from the adsorption of additional hydrogen can be expected as well, but affect the surface electronic properties less than H desorption. [ABSTRACT FROM AUTHOR]

With the advent of the Age of Big Data, resistive random-access memory (RRAM) shows considerable potential for next generation nonvolatile storage technologies owing to its simplified structure, high switching speed, and low power consumption. However, mainstream prepared materials, such as oxides and halide perovskite, face critical issues for practical applications such as switching uniformity and long-term environmental stability. In this work, we report that high carrier mobility material indium phosphide (InP) is prepared as an RRAM medium and is directly bonded to the high thermal conductivity substrate silicon carbide (SiC) at 200 °C, overcoming large (14.9%) lattice mismatch. Importantly, the bonding strength reaches 9.3 MPa, and this high-performance stable RRAM exhibits nonvolatile and reliable switching characteristics including stable endurance (200 cycles) and long data retention (2000 s). Moreover, multilevel storage is also available by modulating RESET stop voltages. This work provides broad possibilities for high-performance RRAM with structures based on traditional semiconductors in the field of nonvolatile storage. [ABSTRACT FROM AUTHOR]

The technology for production one and two-cascade power laser converters was presented in this paper. According to the measurement results of the grown samples, an efficiency of 34.5% was achieved. A promising design of a cascade photoelectric converter is proposed, in which the cascades are connected with using conduction channels based on GaP microcrystallites. [ABSTRACT FROM AUTHOR]

This article presents a study of the mechanism of porous space formation on the surface of single-crystal indium phosphide. The dissolution features of crystals of various types of conductivity and crystallographic orientation of the surface are demonstrated. The attention is focused on the formation of pore chain channels on the surface of n-InP (111). The main stages of the pore formation process are highlighted, which are described according to two competing theories—spontaneous seeding and defect–dislocation mechanism. [ABSTRACT FROM AUTHOR]

Fluorescent indium phosphide (InP) semiconductor quantum dots (QDs) are a promising low-toxicity alternative to cadmium chalcogenide QDs. It is expected that, if comparable optical characteristics are achieved, InP QDs can successfully displace Cd-containing nanocrystals from their traditional applications in optoelectronics and biomedicine. To date, unfortunately, the optical parameters of InP QDs are inferior to those of their Cd-containing counterparts, and the methods of their production require additional optimization. This paper presents the results of experiments on optimizing the synthesis of InP QDs using tris(diethylamino)phosphine as a phosphorus precursor. It has been shown that optimization of the modes of reaction mixture heating during the synthesis allows obtaining highly homogeneous InP QDs with improved optical characteristics. [ABSTRACT FROM AUTHOR]

Utilizing performed research, photoelectric converters of narrow-band radiation (λ ≈ 1.0–1.3 μm) based on InGaAsP/InP heterostructures with an epitaxial p–n junction have been developed and created. Technological regimes that apply of for creating high-quality layers of quaternary InGaAsP solid solutions isoperiodic to indium phosphide in a wide range of compositions by liquid-phase epitaxy have been determined. [ABSTRACT FROM AUTHOR]

The possibility of realizing single-mode emission in quantum-cascade lasers due to modulation of output optical losses in a Fabry–Perot cavity is demonstrated. For the active region of the 7.5–8.0 μm spectral range, the two- phonon resonance design was used, thus, 50 stages and waveguide layers based on indium phosphide made it possible to realize single-mode 7.765 μm lasing at the temperature of 292 K. Side-mode suppression ratio was about 24 dB and remained the same with an increase in the current pumping up to 1.2 of the threshold current values. The coefficient of wavelength shift with temperature (temperature tuning) in the single-mode lasing regime was 0.56 nm/K. [ABSTRACT FROM AUTHOR]

The possibility of fabrication of 4.6 μm spectral range quantum-cascade laser heterostructures by molecular-beam epitaxy technique with non-selective overgrowth by the metalorganic vapour-phase epitaxy is shown. The active region of the laser was formed on the basis of a heteropair of In0.67Ga0.33As/In0.36Al0.64As solid alloys. The waveguide claddings are formed by indium phosphide. The results of surface defects inspection and X-ray diffraction analysis of quantum-cascade laser heterostructures allow to conclude that the structural quality of the heterostructures is high and the estimated value of the root mean square surface roughness does not exceed 0.7 nm. Lasers with four cleaved facets exhibit lasing at room temperature with a relatively low threshold current density of the order of 1 kA/cm2. [ABSTRACT FROM AUTHOR]