B. Amin

Ab initio study of the bandgap engineering of Al1−xGaxN for optoelectronic applications

A theoretical study of Al1−xGaxN, based on the full-potential linearized augmented plane wave method, is used to investigate the variations in the bandgap, optical properties, and nonlinear behavior of the compound with the change in the Ga concentration. It is found that the bandgap decreases with the increase in Ga. A maximum value of 5.50 eV is determined for the bandgap of pure AlN, which reaches a minimum value of 3.0 eV when Al is completely replaced by Ga. The static index of refraction and dielectric constant decreases with the increase in the bandgap of the material, assigning a high index of refraction to pure GaN when compared to pure AlN. The refractive index drops below 1 for higher energy photons, larger than 14 eV. The group velocity of these photons is larger than the vacuum velocity of light. This astonishing result shows that at higher energies the optical properties of the material shifts from linear to nonlinear. Furthermore, frequency dependent reflectivity and absorption coefficients...

Conversion of Direct to Indirect Bandgap and Optical Response of B Substituted InN for Novel Optical Devices Applications

Optical properties of BxIn1 - xN are calculated as a function of the varying concentration of boron and indium. Indium is gradually replaced by boron and optical properties of the resulting materials are studied. The fractional concentration of boron is increased gradually from x = 0 to x = 1 in steps of 0.25. The bandgap increases with the increasing boron concentration, from 0.95 eV for pure InN to 5.6 eV for BN. A unique behavior of BN in zinc-blend phase is observed, that is, it shifts from indirect to direct bandgap semiconductor by the substitution of In on B sites. This behavior can be used to make novel and advanced optical devices. Frequency dependent reflectivity, absorption coefficient, and optical conductivity of BxIn1 - xN are calculated and found to be the constituents concentration dependent. The region of reflectivity, absorption coefficient and optical conductivity shifts from lower frequency into the higher frequency as the material goes from pure InN to pure BN.

Materials properties of out-of-plane heterostructures of MoS2-WSe2 and WS2-MoSe2

Based on first-principles calculations, the materials properties (structural, electronic, vibrational, and optical properties) of out-of-plane heterostructures formed from the transiti on metal dichalcogenides, specifically MoS

Theoretical investigation of half metallicity in Fe/Co/Ni doped ZnSe material systems

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Bandgap investigations and the effect of the In and Al concentration on the optical properties of In x Al 1−x N

-WSe

Optoelectronic Response of GeZn2O4 through the Modified Becke—Johnson Potential

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Linear and nonlinear optical response of MgxZn1−xO: A density functional study

and WS

Intriguing electronic structures and optical properties of two-dimensional van der Waals heterostructures of Zr2CT2 (T = O, F) with MoSe2 and WSe2

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Robust Half-Metallicity in a Chromium-Substituted AlN

-MoSe

Layered graphene/GaS van der Waals heterostructure: Controlling the electronic properties and Schottky barrier by vertical strain

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