Antimonide

About: Antimonide is a research topic. Over the lifetime, 972 publications have been published within this topic receiving 10981 citations. The topic is also known as: antimonides.

Quantum efficiency enhancement of bialkali photocathodes by an atomically thin layer on substrates

Abstract: We report quantum efficiency (QE) enhancements in accelerator technology relevant antimonide photocathodes (K2CsSb) by interfacing them with atomically thin two-dimensional (2D) crystal layers. The enhancement occurs in a reflection mode, when a 2D crystal is placed in between the photocathodes and optically reflective substrates. Specifically, the peak QE at 405 nm (3.1 eV) increases by a relative 10 percent, while the long wavelength response at 633 nm (2.0 eV) increases by a relative 36 percent on average and up to 80 percent at localized hot spot regions when photocathodes are deposited onto graphene coated stainless steel. There is a similar effect for photocathodes deposited on hexagonal boron nitride monolayer coatings using nickel substrates. The enhancement does not occur when reflective substrates are replaced with optically transparent sapphire. Optical transmission, X-ray diffraction (XRD) and X-ray fluorescence (XRF) revealed that thickness, crystal orientation, quality and elemental stoichiometry of photocathodes do not appreciably change due to 2D crystal coatings. These results suggest optical interactions are responsible for the QE enhancements when 2D crystal sublayers are present on reflective substrates, and provide a pathway toward a simple method of QE enhancement in semiconductor photocathodes by an atomically thin 2D crystal on substrates.

Lattice mismatched growth for mid-IR VECSELs

Abstract: We demonstrate a novel epitaxial process for the growth of low-dislocation density GaSb on GaAs. The growth mode involves the formation of large arrays of periodic 90° misfit dislocations at the interface between the two binary alloys which results in a completely strain relieved III-Sb epi-layer without the need for thick buffer layers. This epitaxial process is used for the growth of antimonide active regions directly on GaAs/AlGaAs distributed Bragg Reflectors (DBRs) resulting in 2 μm VECSELs on GaAs substrates.

Tuning the structural and electronic properties of two dimensional boron antimonide with defects and group-III dopants

Abstract: Herein, we systematically investigated the effect of Al, Ga, and In doping and other defects on the structural and electronic properties of 2D-BSb with the first principle density-functional theory (FP-DFT). The 2D-BSb is a planar structure having a direct bandgap value of 0.332 eV. Similarly, the direct bandgap values of B, Sb, and double vacancies are 0.472, 0.374, and 0.341 eV, correspondingly, which are larger than the pristine 2D-BSb structure. Moreover, B/Sb antisite and exchange defects significantly decrease the bandgap of pristine 2D-BSb from the value of 0.332 to 0.137, 0.134, and 0.289 eV, respectively, while the structure preserves a direct bandgap behavior. Alternatively, Al, Ga, and In doping increase the direct bandgap of 2D-BSb structure from 0.332 to 0.425, 0.391, and 0.378 eV, correspondingly. This study might be helpful in providing effective strategies on tuning the electronic bandgap and would be useful for novel optoelectronics and nanoelectronics devices.

First-Order Phase Transition in a New CaCu5-Related Antimonide, CePt5Sb

Abstract: A new CaCu5 related antimonide, CePt5Sb, has been identified. This ternary compound undergoes a structural phase transition at about 80 K according to room- and low-temperature X-ray and neutron di...