Edge mode percolation and equilibration in the topological insulator cadmium arsenide
Abstract Two-dimensional topological insulators can feature one-dimensional charge transport via edge modes, which offer a rich ground for studying exotic quasi-particles and for quantum materials applications. In this work, we use lateral junction devices, defined by nanoscale finger gates, to stud...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Nature Portfolio
2023-11-01
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| Series: | npj Quantum Materials |
| Online Access: | https://doi.org/10.1038/s41535-023-00602-6 |
| _version_ | 1827635700924678144 |
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| author | Simon Munyan Binghao Guo William Huynh Victor Huang Susanne Stemmer |
| author_facet | Simon Munyan Binghao Guo William Huynh Victor Huang Susanne Stemmer |
| author_sort | Simon Munyan |
| collection | DOAJ |
| description | Abstract Two-dimensional topological insulators can feature one-dimensional charge transport via edge modes, which offer a rich ground for studying exotic quasi-particles and for quantum materials applications. In this work, we use lateral junction devices, defined by nanoscale finger gates, to study edge mode transport in the two-dimensional topological insulator Cd3As2. The finger gate can be tuned to transmit an integer number of quantum Hall edge modes and exhibits full equilibration in the bipolar regime. When the Fermi level of the channel crosses a Landau level, reflected modes percolate through the channel, resulting in an anomalous conductance peak. The device does not fully pinch off when the channel is tuned into the topological gap, which is a sign of remnant modes in the channel. These modes are expected from band inversion, while residual bulk conduction associated with the disorder potential may also play a role. |
| first_indexed | 2024-03-09T15:31:12Z |
| format | Article |
| id | doaj.art-6878293aecd44bafb50020c8bbca1c9a |
| institution | Directory Open Access Journal |
| issn | 2397-4648 |
| language | English |
| last_indexed | 2024-03-09T15:31:12Z |
| publishDate | 2023-11-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | npj Quantum Materials |
| spelling | doaj.art-6878293aecd44bafb50020c8bbca1c9a2023-11-26T12:15:17ZengNature Portfolionpj Quantum Materials2397-46482023-11-01811610.1038/s41535-023-00602-6Edge mode percolation and equilibration in the topological insulator cadmium arsenideSimon Munyan0Binghao Guo1William Huynh2Victor Huang3Susanne Stemmer4Materials Department, University of CaliforniaMaterials Department, University of CaliforniaMaterials Department, University of CaliforniaMaterials Department, University of CaliforniaMaterials Department, University of CaliforniaAbstract Two-dimensional topological insulators can feature one-dimensional charge transport via edge modes, which offer a rich ground for studying exotic quasi-particles and for quantum materials applications. In this work, we use lateral junction devices, defined by nanoscale finger gates, to study edge mode transport in the two-dimensional topological insulator Cd3As2. The finger gate can be tuned to transmit an integer number of quantum Hall edge modes and exhibits full equilibration in the bipolar regime. When the Fermi level of the channel crosses a Landau level, reflected modes percolate through the channel, resulting in an anomalous conductance peak. The device does not fully pinch off when the channel is tuned into the topological gap, which is a sign of remnant modes in the channel. These modes are expected from band inversion, while residual bulk conduction associated with the disorder potential may also play a role.https://doi.org/10.1038/s41535-023-00602-6 |
| spellingShingle | Simon Munyan Binghao Guo William Huynh Victor Huang Susanne Stemmer Edge mode percolation and equilibration in the topological insulator cadmium arsenide npj Quantum Materials |
| title | Edge mode percolation and equilibration in the topological insulator cadmium arsenide |
| title_full | Edge mode percolation and equilibration in the topological insulator cadmium arsenide |
| title_fullStr | Edge mode percolation and equilibration in the topological insulator cadmium arsenide |
| title_full_unstemmed | Edge mode percolation and equilibration in the topological insulator cadmium arsenide |
| title_short | Edge mode percolation and equilibration in the topological insulator cadmium arsenide |
| title_sort | edge mode percolation and equilibration in the topological insulator cadmium arsenide |
| url | https://doi.org/10.1038/s41535-023-00602-6 |
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