2026-06-28T14:49:14Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/596422024-08-30T15:58:32Zcom_20.500.14352_14col_20.500.14352_15

00925njm 22002777a 4500 dc Sefrioui, Zouhair author Arias Serna, Diego author Morales, F. author Varela Del Arco, María author León Yebra, Carlos author Escudero, R. author Santamaría Sánchez-Barriga, Jacobo author 2001-01-01 We report on transport and magnetic relaxation measurements of deoxygenated YBa_(2)Cu_(3)O_(7-δ) thin films. Strongly oxygen depleted samples with δ=0.6 are produced to ensure the pure two-dimensional nature of the vortex system. Linear resistivity shows a temperature dependence according to ρ_(lin^(α))exp[-((T_(0)/T)^(p)]. T_(0) takes a value of 230±10 K over the whole field range, and p changes from 1±0.03 at 2 T to 0.70±0.03 at 8 T. For fields higher than 4 T, dissipation in the linear regime (low current densities) is dominated by quantum variable range hopping ~VRH! of vortices. At high current densities and low temperatures, nonlinear dissipation takes place by quantum creep, characterized by a temperature-independent resistivity and by a saturation of the magnetic relaxation rate. 0163-1829 10.1103/PhysRevB.63.054509 https://hdl.handle.net/20.500.14352/59642 http://dx.doi.org/10.1103/PhysRevB.63.054509 http://journals.aps.org/ Evidence for vortex tunnel dissipation in deoxygenated YBa_(2)Cu_(3)O_(6.4) thin films