Spins in Low-Dimensional Materials Systems: Transport, Gate-Control and Conversion

Masashi Shiraishi, Kyoto University

IEEE Magnetics Society Distinguished Lecturer 2020

June 8, 2020

Transport, control and conversion of spins in condensed matters have been pivotal concepts in spintronics. Spin transport is the most fundamental concept to realize spin-dependent phenomena, spin control mainly by gating enables information switching using a spin degree of freedom, and spin conversion allows detection of spins, a dissipative physical quantity. Whilst bulk metallic and semiconducting systems have been to date major material stages to realize the aforementioned concepts, low-dimensional materials systems such as atomically-flat two-dimensional materials [1-3], two-dimensional electron gases formed at an interface of a heterostructure [4,5], topologically-protected Dirac surface states in topological insulators [6,7] and ultrathin films [8] are becoming attractive materials stages to pursue novel spintronic concepts and phenomena. I will introduce the attractiveness of these new materials systems, cover an overview of the central achievements, and focus on recent investigation to pioneer novel spintronic physics in the low-dimensional materials systems.

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[3] A. W. Cummings, S. Roche et al., Giant spin lifetime anisotropy in graphene induced by proximity effects, Phys. Rev. Lett. 119, 206601 (2017).
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[8] S. Dushenko, M. Shiraishi, et al., Tunable inverse spin Hall effect in nanometer-thick platinum films by ionic gating, Nature Commun. 9, 3118 (2018).