Cubic inclusions in hexagonal AlN , GaN , and InN : Electronic states
نویسنده
چکیده
Modern quasiparticle calculations based on hybrid functionals and the GW approximation or a transition-state approach are used to predict natural band discontinuities between wurtzite and zinc-blende polytypes of AlN, GaN, and InN by two alignment methods, a modified Tersoff method for the branch-point energy and the Shockley-Anderson model aligning electrostatic potentials. We find a type-I heterostructure behavior for cubic layers embedded in wurtzite for GaN and InN, while AlN tends to a type-II heterostructure behavior. In addition, the electronic states of wurtzite-zinc-blende superlattices are studied in detail with respect to their energy position and wave-function localization. While the lowest electron states are localized in the cubic inclusion for all nitrides, the localization of the uppermost hole states is less clear but tends to be in the hexagonal matrix. The influence of the built-in internal electric fields is discussed.
منابع مشابه
Study of elastic and piezoelectric properties of two-dimensional hexagonal III-V binary compounds: First-principles calculations
In this work, using plane wave method in the framework of density-functional theory, we calculated clamped-ion and relaxed-ion elasticity, stress and strain piezoelectric independent coefficients for seven stable combinations of honeycomb monolayers XY (X:B,Al,Ga,In ; Y:N,P,As,Sb). The coefficients calculations by two methods of density functional perturbation theory (DFPT) and finite differenc...
متن کاملExact-exchange calculations of the electronic structure of AlN, GaN and InN
The electronic structure of the zincblende (ZB) phase of AlN, GaN and InN has been investigated by using the exact-exchange (EXX) Kohn–Sham density functional theory, with the Ga 3d and In 4d electrons treated both as valence states and as part of the frozen core. Our EXX bandgaps for AlN and GaN (obtained with the semicore Ga 3d electrons included as core states) are found to be in good agreem...
متن کاملFirst principles phase diagram calculations for the wurtzite-structure quasibinary systems SiC-AlN, SiC-GaN and SiC-InN
The cluster-expansion method was used to perform first principles phase diagram calculations for the wurtzite-structure quasibinary systems (SiC)1 X(AlN)X, (SiC)1 X (GaN)X and (SiC)1 X(InN)X; and to model variations of band gaps as functions of bulk compositions and temperature. In SiC-AlN, plane wave pseudopotential formation-energy calculations predict low-energy metastable states with format...
متن کاملFirst-Principles Investigation of Density of States and Electron Density in Wurtzite In0.5Ga0.5 N Alloys with GGA-PBEsol Method
In present work, we have calculated the electronic properties including density of states and electron density for GaN, InN and InxGa1-xN in wurtzite phase for x=0.5. The study is based on density functional theory with full potential linearized augmented plane wave method by generalized gradient approximation for calculating electronic properties. In this report we concluded that InxGa1-xN ba...
متن کاملEnergetics and electronic structure of stacking faults in AlN, GaN, and InN
Basal-plane stacking faults in wurtzite AlN, GaN, and InN are studied using density-functionalpseudopotential calculations. The formation energies follow the trend exhibited for the zinc-blende/wurtzite energy differences in the bulk materials, namely, lowest energy for GaN and highest for AlN. Type-I stacking faults have the lowest energy, followed by type-II stacking faults, and finally extri...
متن کامل