Interplay between s-d exchange interaction and Rashba effect: Spin-polarized transport

Abstract

We investigate the spin-polarized transport properties of a two-dimensional electron gas in a n-type diluted magnetic narrow gap semiconductor quantum well subjected to a perpendicular magnetic and electric field. Interesting beating patterns in the magneto resistance are found which can be tuned significantly by varying the electric field. A resonant enhancement of spin-polarized current is found which is induced by the competition between the s-d exchange interaction and the Rashba effect [Y. A. Bychkov and E. I. Rashba, J. Phys. C 17, 6039 (1984)].

Current-induced spin–orbit torques

“…It has been realized as well that the mechanism described in §3 could be used to exert a torque on the magnetization of an FM layer in contact with a semiconducting channel by absorption of the SO-induced spinpolarization component perpendicular to the FM magnetization at the interface between the two materials [67,68]. More recently, however, it has become clear that the very same SO effect is intrinsic also to an FM [69] and can be used to induce a torque on the local magnetization in a single, uniformly magnetized FM structure [15][16][17] as well as DW motion in FM layers [59]. Here, we focus on such an effect in a uniformly magnetized FM, which we denote as an SO torque in order to distinguish it from the widely investigated STT mechanism, where the SO interaction enters only indirectly through the damping and spin-flip relaxation parameters [70].…”

Ultrafast spin dynamics in II-VI diluted magnetic semiconductors with spin-orbit interaction

“…[10][11][12][13][14][15] The interplay between the exchange interaction characteristic of DMS and the more generic SOI can lead to new possibilities for applications and basic research. [16][17][18][19][20][21] In particular, the spin-orbit torque effect in DMS has attracted much interest in recent years. [22][23][24][25][26][27][28][29] In this article we explore theoretically this interplay by studying the ultrafast spin dynamics of a non-equilibrium electron distribution in the conduction band of II-VI Mndoped semiconductors.…”

Quantum capacitance of MIS structures based on diluted magnetic semiconductors

“…We assume that the magnetic ions are distributed homogeneously in the DMS, and that the extended nature of the electronic wave function spans a large number of magnetic ions, allowing the use of a molecular-field approximation to replace the magnetic-ion spin operator S i with the thermal average S z along the external magnetic field direction. This approach has been proven to be suitable in previous studies [5], [6]. Correspondingly, the exchange interaction in Eq.…”

“…Consequently, a strongly spin-polarized current can be generated even when the carrier spin polarization is vanishingly small [5]. The spin-polarized transport of two-dimensional electron gas (2DEG) formed in a diluted magnetic semiconductor in the presence of Rashba SOI, has been recently investigated [6].…”