Eur. Phys. J. Plus (2018) 133: 442
https://doi.org/10.1140/epjp/i2018-12246-0

Regular Article

Pressure and composition dependence of thermodynamic properties of zinc-blende Al_yGa_1-yAs alloy

¹ VNU University of Education, 144 Xuan Thuy, Cau Giay, Hanoi, Vietnam
² Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi, Vietnam
³ Faculty of Energy, Thuyloi University, 175 Tay Son, Dong Da, Hanoi, Vietnam
⁴ Duy Tan University, 03 Quang Trung, Hai Chau, Danang, Vietnam

^* e-mail: dqkhoa76@gmail.com

Received: 3 February 2018
Accepted: 11 September 2018
Published online: 26 October 2018

Abstract

The moment method in statistical mechanics is applied to study the thermodynamic properties of the zinc-blende Al_yGa_1-yAs compound. The lattice parameter, isothermal bulk modulus, specific heats at the constant volume and constant pressure of the zinc-blende Al_yGa_1-yAs crystal are investigated in detail as functions of pressure and Al composition up to 10 GPa at room temperature. Numerical calculations have been performed using the many-body Pearson-Takai-Halicioglu-Tiller potential to describe atomic interactions in the Al_yGa_1-yAs system. Our work shows that the lattice parameter and specific heats of the Al_yGa_1-yAs alloy increase almost linearly with the Al composition. Nevertheless, when pressure goes up, while lattice parameter and specific heats decrease gradually, the isothermal bulk modulus increases drastically. Present results can be used as reference data for future experiments and theoretical works. Furthermore, this research proposes the potential of statistical moment method on investigation of thermodynamic and mechanical properties of ternary alloys.