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arXiv · 1707.07408

Universal Spin Dynamics in Quantum Wires

E. A. Fajardo·U. Zülicke·R. Winkler
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Abstract

We discuss the universal spin dynamics in quasi one-dimensional systems including the real spin in narrow-gap semiconductors like InAs and InSb, the valley pseudospin in staggered single-layer graphene, and the combination of real spin and valley pseudospin characterizing single-layer transition metal dichalcogenides (TMDCs) such as MoS$_2$, WS$_2$, MoSe$_2$, and WSe$_2$. All these systems can be described by the same Dirac-like Hamiltonian. Spin-dependent observable effects in one of these systems thus have counterparts in each of the other systems. Effects discussed in more detail include equilibrium spin currents, current-induced spin polarization (Edelstein effect), and spin currents generated via adiabatic spin pumping. Our work also suggests that a long-debated spin-dependent correction to the position operator in single-band models should be absent.

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E. A. Fajardo, U. Zülicke, R. Winkler. 2017-10-13. Universal Spin Dynamics in Quantum Wires. https://doi.org/10.1103/physrevb.96.155304

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