Low-dissipation edge currents without edge states
We propose that bulk free carriers in topologically trivial multivalley insulators with nonvanishing Berry curvature can give rise to low-dissipation edge currents, which are squeezed within a distance on the order of the valley diffusion length from the edge. This happens even in the absence of edg...
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| Main Authors: | , |
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| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
2020
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/138038 |
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| Institution: | Nanyang Technological University |
| Language: | English |
| Summary: | We propose that bulk free carriers in topologically trivial multivalley insulators with nonvanishing Berry curvature can give rise to low-dissipation edge currents, which are squeezed within a distance on the order of the valley diffusion length from the edge. This happens even in the absence of edge states [topological (gapless) or otherwise], and when the bulk equilibrium carrier concentration is thermally activated across the gap. Physically, the squeezed edge current arises from the spatially inhomogeneous valley orbital magnetization that develops from valley-density accumulation near the edge. While this current possesses neither topology nor symmetry protection and, as a result, is not immune to dissipation, in clean enough devices it can mimic low-loss ballistic transport. |
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