Spin orbit induced anisotropic giant effective g factor and reduced effective mass in non-magnetic Sn1−xSrxTe mixed crystal.

The binary and ternary telluride systems containing europium as one of the magnetic components exhibit a higher effective g factor and much lower effective mass due to strong spin-orbit and s/p-f hybridized interaction mediated by the dopant impurity. In this communication, we have exploited the same for a ternary mixed crystal S n 1 − x S r x T e , with strontium as the non-magnetic counterpart of europium. We have derived a functional equation within the framework of effective mass representation, accounting for both spin-orbit interaction and the presence of a magnetic field. In the context of k → ⋅ π → model, at first, two MW (Mitchell-Wallis) band edge states are diagonalized properly, and subsequently, the off-band edge states are treated using perturbation up to the k 2 level. We derived the formulas for the effective g factor and effective mass by employing Green's function method, considering the presence of spin-orbit interaction, magnetic field, and Sr impurity and assuming band inversion model as applicable to S n 1 − x S r x T e system. Finally, we conduct a comprehensive examination of the effective g factor, effective mass, and their respective anisotropies in S n 1 − x S r x T e considering their dependence on carrier concentration and impurity levels at T = 300 K. We present extremely elevated effective g factor; g = 2230 , for n − S n 1 − x S r x T e and g = 2160 , for p − S n 1 − x S r x T e respectively with large anisotropies and correspondingly low effective mass m c , v = 0.003 m 0 around x = 0.014 in the concentration range 0.01 × 10 19 cm − 3 to 0.1 × 10 19 cm − 3. Irrespective of the unsaturated electronic shell of Sr , the existence of strong spin-orbit interaction refers to the strong coupling of band edge states across the band minima triggered by substitutional impurity. The occurrence of a substantial effective g factor and low effective mass is unique in such non-magnetic S n 1 − x S r x T e mixed crystal ever reported. • Giant effective g factor; g = 2230 for n − S n 1 − x S r x T e and g = 2160 for p − S n 1 − x S r x T e are reported. • Mostly prominent in telluride and selenide group of binary and ternary compounds like E u T e , E u S e S n 1 − x E u x T e and P b x E u 1 − x T e. • Effective masses as low as m c , v = 0.003 m 0 both for n- S n 1 − x S r x T e and p- S n 1 − x S r x T e are also found. • Calculated parametric anomalies attributes to the strong S.O interaction and band inversion mediated by Sr impurity. • Anisotropic large effective g factor and correspodingly low effective mass makes S n 1 − x S r x T e , a potential choice for spintronics application. [ABSTRACT FROM AUTHOR]