Kedves Máté, Szentpéteri Bálint, Márffy Albin, Tóvári Endre, Papadopoulos Nikos, Rout Prasanna K, Watanabe Kenji, Taniguchi Takashi, Goswami Srijit, Csonka Szabolcs, Makk Péter
Department of Physics, Institute of Physics, Budapest University of Technology and Economics, Műegyetem rkp. 3, Budapest H-1111, Hungary.
MTA-BME Correlated van der Waals Structures Momentum Research Group, Műegyetem rkp. 3, Budapest H-1111, Hungary.
Nano Lett. 2023 Oct 25;23(20):9508-9514. doi: 10.1021/acs.nanolett.3c03029. Epub 2023 Oct 16.
Bilayer graphene (BLG) was recently shown to host a band-inverted phase with unconventional topology emerging from the Ising-type spin-orbit interaction (SOI) induced by the proximity of transition metal dichalcogenides with large intrinsic SOI. Here, we report the stabilization of this band-inverted phase in BLG symmetrically encapsulated in tungsten diselenide (WSe) via hydrostatic pressure. Our observations from low temperature transport measurements are consistent with a single particle model with induced Ising SOI of opposite sign on the two graphene layers. To confirm the strengthening of the inverted phase, we present thermal activation measurements and show that the SOI-induced band gap increases by more than 100% due to the applied pressure. Finally, the investigation of Landau level spectra reveals the dependence of the level-crossings on the applied magnetic field, which further confirms the enhancement of SOI with pressure.
最近研究表明，双层石墨烯（BLG）具有一个能带反转相，其非传统拓扑结构源于由具有大固有自旋轨道相互作用（SOI）的过渡金属二硫属化物的接近诱导的伊辛型自旋轨道相互作用（SOI）。在此，我们报告了通过静水压力在对称封装于二硒化钨（WSe）中的BLG中稳定这种能带反转相。我们从低温输运测量得到的观察结果与一个单粒子模型一致，该模型在两个石墨烯层上诱导出符号相反的伊辛SOI。为了证实反转相的增强，我们进行了热激活测量，并表明由于施加的压力，SOI诱导的带隙增加了超过100%。最后，对朗道能级谱的研究揭示了能级交叉对施加磁场的依赖性，这进一步证实了SOI随压力的增强。
