Low-temperature quantum relaxation of single two-dimensional vortices in an epitaxial Tl2Ba2Ca2Cu3Ox thin film

Time-logarithmic magnetic-relaxation measurements have been obtained in an epitaxial Tl 2 Ba 2 Ca 2 Cu 3 O x thin film for the zero-field cooled and remanent magnetization, with low and moderate applied magnetic fields. With low fields ( H a =50 Oe), the normalized magnetic relaxation rates, S≡‖d(M/...

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Detalhes bibliográficos
Autores: García Santiago, Antoni, Zhang, Xixiang, Tejada Palacios, Javier, Manzel, M., Bruchlos, H.
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:1994
País:España
Recursos:Universidad de Barcelona
Repositório:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/9723
Acesso em linha:https://hdl.handle.net/2445/9723
Access Level:Acceso aberto
Palavra-chave:Superconductors
Efecte túnel
Moviment de vòrtexs
Tunneling (Physics)
Vortex-motion
Descrição
Resumo:Time-logarithmic magnetic-relaxation measurements have been obtained in an epitaxial Tl 2 Ba 2 Ca 2 Cu 3 O x thin film for the zero-field cooled and remanent magnetization, with low and moderate applied magnetic fields. With low fields ( H a =50 Oe), the normalized magnetic relaxation rates, S≡‖d(M/ M i )/d lnt‖, are temperature independent below T≃3.4 K, and the transition from the thermal to the quantum regime appears to be quite sharp. With moderate fields ( H a =500 Oe), the transition becomes smooth and takes place at temperatures higher than with low fields, T≃7 K. This seems to indicate that the mechanism responsible for low-temperature relaxation would be nondissipative Hall tunneling of two-dimensional vortices, rather than dissipative vortex motion.