Transverse resistance in HoBa2Cu3O7−δ single crystals

Abstract

The transverse electrical resistance of HoBa2Cu3O[Formula: see text] single crystals is investigated in the temperature range [Formula: see text] for optimally-doped [Formula: see text] and oxygen-poor [Formula: see text] samples. With decreasing temperature, the resistivity of the optimally-doped samples has been found to transit from the regime of scattering on phonons and defects to the regime of “semiconductor” character and, near [Formula: see text], of the fluctuation conductivity. The oxygen-poor samples have been revealed to exhibit only a variable range hopping conductivity of “semiconductor” character, which near [Formula: see text] transits into the fluctuation conductivity. A significant anisotropy of the residual resistivity and characteristics of the fluctuation conductivity is observed for samples of both types.