Kaifei Kang, Yichen Qiu, Kenji Watanabe, Takashi Taniguchi, Jie Shan, Kin Fai Mak
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引用次数: 0
Abstract
Quantum spin Hall (QSH) insulators are topologically protected phases of matter in two dimensions that can support a pair of helical edge states surrounding an insulating bulk. A higher (even) number of helical edge state pairs is usually not possible in real materials because spin mixing would gap out the edge states. Here, we report experimental evidence for a QSH phase with one and two pairs of helical edge states in twisted bilayer WSe2 at Moiré hole filling factor ν = 2 and 4, respectively. We observe nearly quantized (within 10%) resistance plateaus of and large nonlocal transport at ν = 2 and 4 while the bulk is insulating. The resistance is independent of the out-of-plane magnetic field and increases under an in-plane magnetic field. The results agree with quantum transport of helical edge states in a material with high spin Chern bands protected by Ising spin conservation symmetry.
期刊介绍：
Nano Letters serves as a dynamic platform for promptly disseminating original results in fundamental, applied, and emerging research across all facets of nanoscience and nanotechnology. A pivotal criterion for inclusion within Nano Letters is the convergence of at least two different areas or disciplines, ensuring a rich interdisciplinary scope. The journal is dedicated to fostering exploration in diverse areas, including:
- Experimental and theoretical findings on physical, chemical, and biological phenomena at the nanoscale
- Synthesis, characterization, and processing of organic, inorganic, polymer, and hybrid nanomaterials through physical, chemical, and biological methodologies
- Modeling and simulation of synthetic, assembly, and interaction processes
- Realization of integrated nanostructures and nano-engineered devices exhibiting advanced performance
- Applications of nanoscale materials in living and environmental systems
Nano Letters is committed to advancing and showcasing groundbreaking research that intersects various domains, fostering innovation and collaboration in the ever-evolving field of nanoscience and nanotechnology.
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