The structural, elastic, electronic, magnetic and optical properties of the Zn0.75V0.25X (X = S, Se or Te).

The structural, elastic, electronic, magnetic and optical properties of the Zn_0.75V_0.25X (X = S, Se or Te) have been investigated by the spin-polarized first-principles calculations. The optimized lattice constant increases with the increasing anions radius of S²⁻, Se²⁻ and Te²⁻. All the Zn_0.75V_0.25X systems show the ductile and half-metallic characters. The spin exchange splitting energy Δx(d)<inline-graphic></inline-graphic> increases but the absolute value of the exchange splitting energy Δx(pd)<inline-graphic></inline-graphic> decreases for Zn_0.75V_0.25S, Zn_0.75V_0.25Se and Zn_0.75V_0.25Te successively, and the p-d exchange constant N0β<inline-graphic></inline-graphic> is greater than s-d exchange constant N0α<inline-graphic></inline-graphic>. The static dielectric constants ε1(0)<inline-graphic></inline-graphic>, the maximum value of ε2(ω)<inline-graphic></inline-graphic>, static refractive indexes n(0)<inline-graphic></inline-graphic> and the maximum value of k(ω)<inline-graphic></inline-graphic> get the biggest values for Zn_0.75V_0.25Se among Zn_0.75V_0.25X (X = S, Se or Te). Compared with pure ZnX, the new absorption peaks occur in the energy range of 0-1.4 eV for Zn_0.75V_0.25X systems. The results provide a certain degree of helpful theoretical guidance for the application of the Zn_0.75V_0.25X in spintronics devices and optical detectors. [ABSTRACT FROM AUTHOR]