The magnetic and optical properties of Zr doped GaSb: the first-principles calculation study

The magnetic and optical properties of Zr doped GaSb were studied by the first-principles calculation. The results indicated that both Zr-Ga and Zr-Sb substitutions can introduce 1 mu ( B ) total magnetic moments, but the formation energy of Zr-Sb is larger. The magnetic couplings between two Zr-Ga substitutions are ferromagnetic (FM) with long range. Zr can enhance the absorption of photons in the visible and infrared (IR) regions, improve the static dielectric constant and photocatalytic performance. Although moments induced by Zr-Ga are not affected by strains, the parts contributed by Zr-4d increased/decreased with enlarging tensile/compressive strains. The FM interaction strength is enhanced with magnifying compressive strains and weakened with increasing tensile strains for our considered structures. Moreover, strains make optical curves of Zr doped GaSb move to low energy region slightly. These results indicate that strains may be an effective routine to enhance FM interaction strength and photocatalytic performance of the GaSb:Zr system.