Inverse spin galvanic effect in the presence of impurity spin-orbit scattering: a diagrammatic approach
Amin Maleki, Roberto Raimondi
备注:
14 pages, 1 figure, invited paper for a special issue of Condensed Matter (MDPI) on "Control and Enhancement of Quantum Coherence in Nanostructured Materials"
Spin-charge interconversion is currently the focus of intensive experimental and theoretical research both for its intrinsic interest and for its potential exploitation in the realization of new spintronic functionalities. Spin-orbit coupling is one of the key microscopic mechanisms to couple charge currents and spin polarizations. The Rashba spin-orbit coupling in a two-dimensional electron gas has been shown to give rise to the inverse spin galvanic effect, i.e. the generation of a non-equilibrium spin polarization by a charge current. Whereas the Rashba model may be applied to the interpretation of experimental results in many cases, in general in a given real physical system spin-orbit coupling also occurs due other mechanisms such as Dresselhaus bulk inversion asymmetry and scattering from impurities. In this work we consider the inverse spin galvanic effect in the presence of Rashba, Dresselhaus and impurity spin-orbit scattering. We find that the size and form of the inverse spin galvanic effect is greatly modified by the presence of the various sources of spin-orbit coupling. Indeed, spin-orbit coupling affects the spin relaxation time by adding the Elliott-Yafet mechanism to the Dyakonov-Perel and, furthermore, it changes the non-equilibrium value of the current-induced spin polarization by introducing a new spin generation torque. We use a diagrammatic Kubo formula approach to evaluate the spin polarization-charge current response function. We finally comment about the relevance of our results for the interpretation of experimental results.
Real-Time Dynamics in Quantum Impurity Models with Diagrammatic Monte Carlo
我们扩展了最近开发的实时Diagrammatic Monte Carlo方法,在其杂交扩展配方,完整的Kadanoff-Baym-Keldysh轮廓。这使我们能够从任意的,甚至相互作用的,初始密度矩阵开始研究相关杂质模型的实时动态。作为概念证明,我们应用该算法研究了Anderson杂质模型中局域量子猝灭后的非平衡动力学。作为量子杂质模型中实时动力学的一种完全通用的方法,它可以用作非平衡动力学平均场论的求解器。