Hysteretic effects in calorimetric measurements of the vortex melting transition in high-purity YBa2Cu3O7-delta single crystals

摘要

We present specific heat measurements in high-purity, detwinned YBa2Cu3O7-delta single crystals, with a state-of-the-art, high-resolution, AC calorimetric setup. Using a unique feature of the AC calorimetry, we demonstrate the existence of hysteretic effects at the vortex melting transition in specific heat measurements, a much-needed element fur establishing the first-order character of melting. (C) 2000 Elsevier Science B.V. All rights reserved. [References: 15]