arXiv subjects

A. S. Verma

Publications and source records attributed to A. S. Verma.

4 recordsLinked to original sources

arXiv2026

Halide substitution effects on the photovoltaic properties of Ca$_3$PX$_3$ (X = F, Cl, Br, I) perovskites: advancing solar cell efficiency

Herein, the fundamental physical characteristics like structural, electronic, optical parameters of the Ca$_3$PX$_3$ (X = F, Cl, Br, I) materials have been investigated for their potential optoelectronic applications, particularly for solar cells and related devices. To the crystallographic investigations, Ca$_3$PI$_3$ has the most stable configuration among all investigated materials. From the band structure analyses of these materials indicate that all materials have a direct bandgap in the range of 2.0 eV to 3.788 eV, which makes them ideal for light absorption. For the photovoltaic applications, we have analysed first-principles spectroscopic screening limited maximum efficiency (SLME) which confirms that the Ca$_3$PI$_3$ material exhibits the highest solar cell efficiency 29.6% and Ca$_3$PF$_3$ and shows lower efficiency for solar cell suitability 0.6%. Thus, these results demonstrate the real potential and abilities of halide substitution to tune the materials for particular optoelectronic devices.

cond-mat.mtrl-sci↗

arXiv2025

Ab initio study of mechanical and functional properties of novel CaZnC and CaZnSi half-Heusler materials

This research work introduces the DFT through FP-LAPW+lo technique in WIEN2k software to obtain information about structural, thermoelectric, and optoelectronic characteristics of CaZnC and CaZnSi materials. The structural optimization was performed using PBE-GGA functional, while the rest of the characteristics were obtained with the PBE-GGA + TB-mBJ approach. The thermoelectric parameters were evaluated using BoltzTraP software. The elastic constants and other mechanical parameters were computed by utilizing the ELAST code within the WIEN2k software, while the thermodynamic characteristics were evaluated using the Gibbs2 program. The findings show a correlation between atomic composition and lattice dimensions while finding that CaZnC has a direct ($Γ$-$Γ$) band gap of $1.186$ eV, whereas CaZnSi has an indirect ($Γ$-$X$) band gap of $1.067$ eV. The optical studies of the compounds show potential applications for photovoltaics while the thermoelectric results find optimized power factors and figure of merit values for energy conversion performance. The elastic parameters of CaZnC and CaZnSi demonstrate material stability and brittleness. Lastly, the thermodynamic evaluations provide information about the thermal mechanism and disorder of the materials. As a result, this research work provides significant advancements in the understanding of the fundamentals of these compounds and highlights their promising applications in renewable energy technologies.

cond-mat.mtrl-sci↗

arXiv2010

Cohesive energy of zinc blende (AIIIBV and AIIBVI) structured solids

In this letter we present an expression relating the cohesive energy for the A3B5 and A2B6 semiconductors with the product of their ionic charges and nearest neighbor distance. The cohesive energy values of these solids exhibits a linear relationship when plotted on a log-log scale against the nearest neighbor distance, but fall on different straight lines according to the ionic charge product of the solids. A good agreement has been found between the experimental and calculated values of the cohesive energy for A3B5 and A2B6 semiconductors.

cond-mat.mtrl-sci↗

arXiv2010

Inherent properties of binary tetrahedral semiconductors

A new approach utilising the concept of ionic charge theory has been used to explain the inherent properties such as lattice thermal conductivity and bulk modulus of 3,5 and 2,6 semiconductors. The lattice thermal conductivity of these semiconductors exhibit a linear relationship when plotted on a log scale against the nearest neighbour distance but fall on two straight lines according to the product of the ionic charge of the compounds. On the basis of this result a simple relationship of lattice thermal conductivity with bulk modulus is proposed and used to estimate the bulk modulus of these semiconductors. A fairly good agreement has been found between the experimantal and calculated values of these parameters for zinc blende structured solids.

cond-mat.mtrl-sci↗