相关论文: Band Alignments of Emerging Wurtzite BAlN and BGaN…
Wurtzite LaN (wz-LaN) is a semiconducting nitride with favorable piezoelectric and ferroelectric properties, making it promising for applications in electronics. We use first-principles density functional theory with a hybrid functional to…
Polarization arising from non-centrosymmetric wurtzite lattice underpins the physics and functionality of gallium nitride (GaN)-the most produced semiconductor materials second only to silicon. However, recent direct experimental…
Using comprehensive x-ray reciprocal space mapping, we establish the precise lattice-matching composition for wurtzite $Sc_xAl_{1-x}N$ layers on (0001) GaN to be x = 0.14+/-0.01. 100-nm thick $Sc_xAl_{1-x}N$ films (x = 0.09 - 0.19) were…
Tuning thermal transport in semiconductor nanostructures is of great significance for thermal management in information and power electronics. With excellent transport properties, such as ballistic transport, immunity to point defects and…
Crystal phase semiconductor heterostructures allow for electron confinement without uncertainties caused by chemical intermixing found in material heterostructures and are candidates for next generation optoelectronics devices ranging from…
We investigate exciton states theoretically in strained GaN/AlN quantum dots with wurtzite (WZ) and zinc-blende (ZB) crystal structures, as well as strained WZ GaN/AlGaN quantum dots. We show that the strain field significantly modifies the…
The Mg2X (X=Si, Ge, Sn) based alloy is an eco-friendly thermoelectric material for mid-temperature applications. The Mg2Si1-xSnx and Mg2Ge1-xSnx alloys can be phase-separated into Si(Ge)- and Sn-rich phases during material synthesis,…
A theoretical study of Al(1-x)Ga(x)N, based on full-potential linearized augmented plane wave method, is used to investigate the variations in the bandgap, optical properties and non-linear behavior of the compound with the variation of Ga…
Unlike c-plane nitrides, ``non-polar" nitrides grown in e.g. the a-plane or m-plane orientation encounter anisotropic in-plane strain due to the anisotropy in the lattice and thermal mismatch with the substrate or buffer layer. Such…
The lattice mismatch between AlGaN and AlN substrates limits the design and efficiency of UV LEDs, but it can be mitigated by the co-incorporation of boron. We employ hybrid density functional theory to investigate the thermodynamic,…
Boron arsenide, the typically-ignored member of the III-V arsenide series BAs-AlAs-GaAs-InAs is found to resemble silicon electronically: its Gamma conduction band minimum is p-like (Gamma_15), not s-like (Gamma_1c), it has an X_1c-like…
The unprecedented wide bandgap tunability (~1 eV) of Al$_x$In$_{1-x}$As$_y$Sb$_{1-y}$ latticed-matched to GaSb enables the fabrication of photodetectors over a wide range from near-infrared to mid-infrared. In this paper, the valence…
In this paper, we analyze the dependence of elastic constants c_ij on composition for random wurtzite quater- nary AlGayInN alloy in the whole concentration range. The study takes as its starting point the c_ij parameters for zinc blende…
Ternary and quaternary cubic c-AlxIn1-xN/GaN and c-AlxGayIn1-x-y/GaN heterostructures lattice-matched to c-GaN on freestanding 3C-SiC substrates were grown by plasma-assisted molecular beam epitaxy. The c-AlxGayIn1-x-y alloy permits the…
Boron (B) containing III-nitride materials, such as wurtzite (B,Ga)N alloys, have recently attracted significant interest to tailor the electronic and optical properties of optoelectronic devices operating in the visible and ultraviolet…
The optical properties of BAlN and BGaN ternary alloys are investigated using first-principle calculation. Hybrid density functional theory is applied to determine the refractive indices of different alloys. A peculiar non-linear behavior…
Raman measurements are performed on defect-free wurzite GaP nanowires. Resonance Raman measurements are carried out over the excitation energy range between 2.19 and 2.71 eV. Resonances at 2.38 eV and 2.67 eV of the E1(LO) mode and at 2.67…
The ground state structures of the A$_x$B$_{1-x}$C wurtzite (WZ) alloys with $x=$0.25, 0.5, and 0.75 are revealed by a ground state search using the valence-force field model and density-functional theory total energy calculations. It is…
AlN-based alloys find widespread application in high-power microelectronics, optoelectronics, and electromechanics. The realization of ferroelectricity in wurtzite AlN-based heterostructural alloys has opened up the possibility of directly…
We use polarized photocurrent spectroscopy in a nanowire device to investigate the band structure of hexagonal Wurtzite InAs. Signatures of optical transitions between four valence bands and two conduction bands are observed which are…