| Autor: |
R. L. Willett, K. Shtengel, C. Nayak, L. N. Pfeiffer, Y. J. Chung, M. L. Peabody, K. W. Baldwin, K. W. West |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Physical Review X, Vol 13, Iss 1, p 011028 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2160-3308 |
| DOI: |
10.1103/PhysRevX.13.011028 |
| Popis: |
The quantum Hall states at filling factors ν=5/2 and 7/2 are expected to have Abelian charge-e/2 quasiparticles and non-Abelian charge-e/4 quasiparticles. The non-Abelian statistics of the latter is predicted to display a striking interferometric signature, the even-odd effect. By measuring resistance oscillations as a function of the magnetic field in Fabry-Pérot interferometers using new high-purity heterostructures, we for the first time report experimental evidence for the non-Abelian nature of excitations at ν=7/2. At both ν=5/2 and 7/2, we also examine, for the first time, the fermion parity, a topological quantum number of an even number of non-Abelian quasiparticles. The phase of observed e/4 oscillations is reproducible and stable over long times (hours) near both filling factors, indicating stability of the fermion parity. At both fractions, when phase fluctuations are observed, they are predominantly π phase flips, consistent with either fermion parity change or change in the number of the enclosed e/4 quasiparticles. We also examine lower-frequency oscillations attributable to Abelian interference processes in both states. Taken together, these results constitute new evidence for the non-Abelian nature of e/4 quasiparticles; the observed lifetime of their combined fermion parity further strengthens the case for their utility for topological quantum computation. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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