Calculation of Curie Temperature and Carriers Effective Masses of (Ga, Mn)As Diluted Magnetic Semiconductor from the Eight-Band k.p Model

An important step toward the development of spintronic information processing, transfer, and storage devices is the discovery of a dilute magnetic semiconductor (DMS) that demonstrates carrier-mediated ferromagnetism and maintains its magnetic properties above room temperature. Despite considerable progress made in recent decades, the maximum Curie temperature (∼200 K) remains well below room temperature. Mndoped GaAs are among the various diluted magnetic semiconductor materials that have been studied and have emerged as one of the most promising contenders for technological usage. The key characteristic of GaMnAs is its ferromagnetic properties, which are critical for spintronic devices. The primary goal of this work is to compute two critical properties of GaMnAs: the effective masses and the Curie temperature. The 8-band k.p model put forth by Kane was utilized to compile the GaMnAs band parameters using a MATLAB program. Our calculations are based on Lowdin perturbation theory, where spin-orbit, sp- d exchange interaction, and biaxial strain are taken into account. We calculated the Curie temperature of the GaMnAs alloy, within the mean-field approach based on the Zener model. Our findings demonstrated a direct proportionality relationship between the Curie temperature and the hole concentration ( p ) in GaMnAs. Moreover, we looked into how the Mn content and strain affected the effective masses of electrons, heavy, and light holes that were calculated for various crystallographic directions in GaMnAs. The effective masses that were calculated were highly dependent on the Mn content, which ranged from 1% to 5%, and the strain, which varied from −2% (tensile strain) to 2% (compressive strain).