Low-temperature magnetic relaxation inYBa2Cu3O7−δ: Evidence for quantum tunneling of vortices
| Autor: | L. Fruchter, A. P. Malozemoff, J. Sanchez, Marcin Konczykowski, I.A. Campbell, F. Holtzberg, R. Griessen |
|---|---|
| Rok vydání: | 1991 |
| Předmět: | |
| Zdroj: | Physical Review B. 43:8709-8712 |
| ISSN: | 1095-3795 0163-1829 |
| DOI: | 10.1103/physrevb.43.8709 |
| Popis: | Hall-probe measurements of an ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ crystal in the range 0.1--1 K show a temperature-independent time-logarithmic magnetic relaxation. These results rule out conventional thermally activated flux creep, which predicts a ${\mathit{T}}^{2/3}$ dependence at the lowest temperatures if one takes into account the dependence of the barrier on driving force in a simple one-dimensional model. They are consistent with a phenomenological theory assuming a quantum tunneling process for vortex kink motion. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|