Mach-Zehnder interferometry using spin- and valley-polarized quantum Hall edge states in graphene
| Autor: | Amir Yacoby, Takashi Taniguchi, Javier Sanchez-Yamagishi, Pablo Jarillo-Herrero, Bertrand I. Halperin, Toeno van der Sar, Di S. Wei, Kenji Watanabe |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Dephasing
FOS: Physical sciences Physics::Optics 02 engineering and technology Quantum entanglement Quantum Hall effect Mach–Zehnder interferometer 01 natural sciences Condensed Matter::Superconductivity Mesoscale and Nanoscale Physics (cond-mat.mes-hall) 0103 physical sciences Astronomical interferometer 010306 general physics Mathematics::Symplectic Geometry Research Articles Quantum well Physics Quantum Physics Multidisciplinary Condensed Matter - Mesoscale and Nanoscale Physics Condensed matter physics SciAdv r-articles Macroscopic quantum phenomena Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 021001 nanoscience & nanotechnology 3. Good health Interferometry Physical Sciences 0210 nano-technology Research Article |
| Zdroj: | Science Advances |
| ISSN: | 2375-2548 |
| Popis: | Confined to a two-dimensional plane, electrons in a strong magnetic field travel along the edge in one-dimensional quantum Hall channels that are protected against backscattering. These channels can be used as solid-state analogues of monochromatic beams of light, providing a unique platform for studying electron interference. Electron interferometry is regarded as one of the most promising routes for studying fractional and non-Abelian statistics and quantum entanglement via two-particle interference. However, creating an edge-channel interferometer in which electron-electron interactions play an important role requires a clean system and long phase coherence lengths. Here we realize electronic Mach-Zehnder interferometers with record visibilities of up to 98% using spin- and valley-polarized edge channels that co-propagate along a PN junction in graphene. We find that inter-channel scattering between same-spin edge channels along the physical graphene edge can be used to form beamsplitters, while the absence of inter-channel scattering along gate-defined interfaces can be used to form isolated interferometer arms. Surprisingly, our interferometer is robust to dephasing effects at energies an order of magnitude larger than observed in pioneering experiments on GaAs/AlGaAs quantum wells. Our results shed light on the nature of edge-channel equilibration and open up new possibilities for studying exotic electron statistics and quantum phenomena. 18 pages, 11 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|