Modification by high pressure of fluctuation paraconductivity of underdoped HoBa2Cu3O7-δ single crystals

Abstract

In this work, we investigate the effect of high pressure on the conductivity in the basal plane of the high temperature super conducting (HTSC) single crystals HoBa 2 Cu 3 O 7-d . It is determined that the excess conductivity Dr(T) of the HoBa 2 Cu 3 O 7-d single crystals in the temperature interval near the critical temperature (T c ) is described within the framework of the Aslamazov-Larkin theoretical model. It is shown that the evolution of the transverse coherence length n c (0) in the case of application/ removal of high pressure is largely determined by the ''relaxation'' pressure effect during prolonged exposure of the sample under load at room temperature.

Effect of electron irradiation on the fluctuation conductivity in YBa2Cu3O7−δ single crystals

“…The question of the effect of dimensionality on the formation of the superconducting state in high-temperature superconducting cuprates (HTSC) remains open, despite the intense experimental and theoretical studies carried out in the last 30 years [1][2][3]. As it is established [1,4], the large penetration depth, the short coherence length and the layered structure contribute to the appearance of an anomalously wide region of excess conductivity (Δσ) in HTSC compounds in the ρ ab (T) dependences (in the basal plane).…”