报告题目:Ising superconductivity, Majorana fermions and spin valley Hall effect in transition metal dichalcogenides
报 告 人:LAW, Kam Tuen, Hong Kong University of Science and Technology
报告时间:2018-01-11 16:00
报告地点:郑裕彤讲堂
报告摘要:Ising superconductors with in-plane upper critical fields several times higher than the Pauli limits have been discovered in transition metal dichacogenides such as MoS2 and NbSe2 thin films [1-3]. These Ising superconductors have very strong Ising spin-orbit couplings (SOC), in the order of 10 to 100meV, which pin electron spins to the out-of-plane directions. This is in contrast to Rashba SOC which pins electron spins to in-plane directions. Here, we explain how Ising SOC can enhance the in-plane upper critical field of Ising superconductors [1-3] and be used to create Majorana fermions [4]. We will also discuss a spin-triplet nodal superconducting phase in gated MoS2. At the end of the talk, I will discuss a new mechanism of valley Hall effect induced by Ising and Rashba SOC. We call this effect spin valley Hall effect [5].
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3. Y Saito et al. Nature Physics 12, 144-149 (2016).
4. Benjamin T. Zhou, Noah F.Q. Yuan, Hong-Liang Jiang and K. T. Law, Phys. Rev. B 93, 180501 R (2016).
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