Spin dynamics for wave packets in Rashba systems

Abstract

We explore spin dynamics for localized wave packets in Rashba systems using spin quantum propagators. We derive exact ͑one-dimensional͒ and approximate ͑two-dimensional͒ analytic expressions for the propagators and apply them to Gaussian wave packets to obtain localized solutions of systems manifesting Rashba interactions. We observe and describe the evolution of the wave packets. We identify characteristic structures in the wave-packet evolution and look for features with specific spintronics applications such as spin separation and spin accumulation. We discuss the relative importance of those features as a function of the Rashba coupling strength ␣ and the width of the wave packet w. In particular, we find a trade off between spatial oscillation and global separation of the spin when varying ␣ and w.

Stern-Gerlach dynamics with quantum propagators

“…Although some of the results presented below depart from the standard SGE, the specifics are different, and the study of their dependence on the choice of parameters allows us to control their presence to some extent. In particular we find some features that are reminiscent of spin-orbit coupling dynamics [27].…”

“…Our goal is to extend some of these methods to spin-dependent potentials of the SG type, that is, potentials combining spin under the form of Pauli matrices and coordinates through magnetic fields that are linear in the coordinates. Some spin-orbit potentials combining spin and momentum have become very important in the area of spintronics [35][36][37] and analytic spin propagators have been obtained in this case also [27]. Once we have constructed the propagators, we apply them to localized Gaussian wave packets and follow the evolution of the spin dynamics.…”

Thermoelectric probe for the Rashba spin–orbit interaction strength in a two dimensional electron gas

“…This is due to its possible applications in spintronics devices [2][3][4]. The SOI is responsible for other interesting effects like the spin Hall effect [5], spin dynamics and zitterbewegung [6][7][8]. In narrow gap semiconductor heterostructures, the dominant Rashba SOI [9,10] appears due to the asymmetric quantum wells.…”