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Predicting and designing highly gas‐sensitive semiconductors is crucial for solving growing environmental problems. Herein, four lateral heterostructures (LHSs), As6/Sb6 AC‐/ZZ‐LHSs and Sb6/Bi6 AC‐/ZZ‐LHSs, are constructed. The adsorption of NO molecule on these LHSs is investigated using first‐principle calculations. The results indicate that the adsorption of NO molecule on As6/Sb6 LHS with armchair (AC) interface is physisorption, whereas NO molecule is chemically adsorbed on As6/Sb6 LHS with zigzag (ZZ) interface and Sb6/Bi6 AC‐/ZZ‐LHSs, with strong adsorption energy and large charge transfer. All LHSs act as charge donors for the NO molecule. Meanwhile, the adsorption of NO molecule causes a significant change in the electronic properties of As6/Sb6 ZZ‐LHS and Sb6/Bi6 AC‐/ZZ‐LHSs, which shows that these LHSs have great potential for application in NO gas sensors. [ABSTRACT FROM AUTHOR]

Identifying interfacial properties and discussing optical properties of antimony‐based type II superlattices are the key factors for developing high performance of infrared optoelectronic devices. Herein, the multi‐epitaxy‐layered structure of a mid‐wavelength‐responsive infrared detector with an InAs/InAsSb superlattice as an active area layer is grown and investigated. High‐resolution X‐ray diffraction, high‐resolution transmission electron microscopy, and the geometric phase analysis indicate epitaxial layers of high crystalline quality and small lattice mismatches. The electric field results obtained by differential phase contrast scanning transmission electron microscopy further confirm the sharp interface states and good periodic structure of the as‐grown samples. The photoluminescence spectrum shows that the photoluminescence signal center is 5.4 μm at 75 K, even at 320 K, the sample still maintains a photoluminescence signal of 6.2 μm. [ABSTRACT FROM AUTHOR]

2D material structures have drawn much attention because of the unique characteristics of carriers confined in 2D planes. Various structures have been fabricated for high‐performance optoelectronic devices. Herein, via first principles, lateral heterostructures (LHSs) based on antimony (Sb) and bismuth (Bi) are predicted and band structures affected under strain are calculated. For Sb/Bi LHSs, zigzag and armchair atomic configurations are considered. By altering the number of atoms on two sides of the heterostructures, the Sb/Bi LHSs exhibit narrow bandgaps. Moreover, external compressive and tensile strains induce transitions from indirect to direct band structures and further compress the bandgap energy into the midinfrared range. Partial density‐of‐states analysis indicates that, under the applied strains, the valence band mainly comprises Bi 6p states and Sb 5p states. In addition, charge density distributions indicate that electrons are localized at Bi atoms, whereas holes are localized at Sb atoms, thus exhibiting spatial separation of carriers. A narrow‐bandgap material in which the band structure and electronic structure characteristics have great potential for infrared optoelectronic applications is proposed herein. [ABSTRACT FROM AUTHOR]

As an important candidate for novel infrared semiconductor lasers, the optical properties of GaAsSb-based multiple quantum wells (MQWs) are crucial. The temperature- and excitation power-dependent photoluminescence (PL) spectra of the GaAs0.92Sb0.08/Al0.2Ga0.8As MQWs, which were grown by molecular beam epitaxy, were investigated and are detailed in this work. Two competitive peaks were observed from 40 K to 90 K. The peak located at the low-energy shoulder was confirmed to be localized states emission (LE) and the high-energy side peak was confirmed to be free-carrier emission by its temperature-dependent emission peak position. It is observed that the LE peak exhibited a blueshift with the increase of laser excitation power, which can be ascribed to the band filling effect of localized states. Our studies have great significance for application of GaAsSb-based MQWs in infrared semiconductor lasers. [ABSTRACT FROM AUTHOR]

Fabrication and Characterization of an InAs(Sb)/InxGa1-xAsySb1-y Type-II Superlattice A novel InAs(Sb)/In SB I x i sb Ga SB 1- I x i sb As SB I y i sb Sb SB 1- I y i sb superlattice with high-indium-content In SB I x i sb Ga SB 1- I x i sb As SB I y i sb Sb SB 1- I y i sb in the immiscibility gap has been designed and fabricated through the fractional monolayer alloy growth method by Peng Du et al. (article number 1900474). Compared to the InAs/GaSb superlattice, this neoteric superlattice InAs(Sb)/In SB I x i sb Ga SB 1- I x i sb As SB I y i sb Sb SB 1- I y i sb exhibits a flexible miniband engineering ability and high luminescence property, which would have great potential applications in infrared optoelectronic devices. [Extracted from the article]

Infrared optoelectronic devices based on type‐II superlattice structures of III–V semiconductor materials have progressed significantly during the past decades. Exploring and further expanding the material space is of great significance for the development of infrared applications. Herein, a superlattice structure based on InAs(Sb)/InxGa1−xAsySb1−y grown using a fractional monolayer alloy process to control the superlattice composition and structure is presented. High‐order satellite peaks with a narrow full width at half maximum (31 arcs) in the X‐ray diffraction patterns indicate the good crystal quality of the superlattices. Transmission electron microscopy (TEM) with energy‐dispersive spectroscopy (EDS) analysis validate the fractional monolayer alloy growth method. Photoluminescence measurements and k·p model calculations reveal the superior optical properties of the superlattice (sevenfold higher intensity than that of InAs/GaSb). In addition, the flexible control over the superlattice structure afforded by the method allows miniband engineering to cover the mid‐wavelength and long‐wavelength infrared regions. This work highlights the great potential of InAs(Sb)/InxGa1−xAsySb1−y superlattices in infrared optoelectronic devices. [ABSTRACT FROM AUTHOR]

No abstract is available for this article. [ABSTRACT FROM AUTHOR]