| Title | Evidence for a topological excitonic insulator in InAs/GaSb bilayers |
| Authors | Du, Lingjie Li, Xinwei Lou, Wenkai Sullivan, Gerard Chang, Kai Kono, Junichiro Du, Rui-Rui |
| Affiliation | Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA. Rice Univ, Dept Elect & Comp Engn, Houston, TX 77005 USA. Chinese Acad Sci, Inst Semicond, SKLSM, Beijing 100083, Peoples R China. Teledyne Sci & Imaging, Thousand Oaks, CA 91630 USA. Rice Univ, Dept Mat Sci & NanoEngn, Houston, TX 77005 USA. Peking Univ, ICQM, Beijing 10083, Peoples R China. Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA. Kono, J (reprint author), Rice Univ, Dept Elect & Comp Engn, Houston, TX 77005 USA. Chang, K (reprint author), Chinese Acad Sci, Inst Semicond, SKLSM, Beijing 100083, Peoples R China. Kono, J (reprint author), Rice Univ, Dept Mat Sci & NanoEngn, Houston, TX 77005 USA. Du, RR (reprint author), Peking Univ, ICQM, Beijing 10083, Peoples R China. |
| Keywords | QUANTUM-WELL STRUCTURES ELECTRONS STATE CONDENSATION TRANSITION SYSTEMS PHASE FIELD HOLES |
| Issue Date | 2017 |
| Publisher | NATURE COMMUNICATIONS |
| Citation | NATURE COMMUNICATIONS. 2017, 8. |
| Abstract | Electron-hole pairing can occur in a dilute semimetal, transforming the system into an excitonic insulator state in which a gap spontaneously appears at the Fermi surface, analogous to a Bardeen-Cooper-Schrieffer (BCS) superconductor. Here, we report optical spectroscopic and electronic transport evidence for the formation of an excitonic insulator gap in an inverted InAs/GaSb quantum-well system at low temperatures and low electron-hole densities. Terahertz transmission spectra exhibit two absorption lines that are quantitatively consistent with predictions from the pair-breaking excitation dispersion calculated based on the BCS gap equation. Low-temperature electronic transport measurements reveal a gap of similar to 2 meV (or similar to 25 K) with a critical temperature of similar to 10 K in the bulk, together with quantized edge conductance, suggesting the occurrence of a topological excitonic insulator phase. |
| URI | http://hdl.handle.net/20.500.11897/500446 |
| ISSN | 2041-1723 |
| DOI | 10.1038/s41467-017-01988-1 |
| Indexed | SCI(E) |
| Appears in Collections: | 待认领 |
