Thermal conductivity of impurity-doped high-Tc superconductors

✍ Scribed by S.T. Ting; P. Pernambuco-Wise; J.E. Crow

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 318 KB
• Volume: 186-188
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/0921-4526(93)90773-y

✦ Synopsis

The thermal conductivity K(T) of polycrystalline YBa2(Cu ~ xNx)307 with N=Zn and AI (0~<x~<0.1) and YI yMyBa2Cu307 with M = Pr and Gd (0 ~< y ~< 1.0) has been measured for temperatures 1.2 ~< T ~< 200 K. In the undoped samples, K(T) decreases slightly with decreasing temperature above To, with a strong enhancement of K(T) below 7".

reaching a maximum at -50K followed by a sharp decrease. Doping with Zn and Pr, which have been shown to dramatically disturb the superconductivity, rapidly depresses the maximum in K(T) even at concentrations that remain superconducting. This effect is not as dramatic for AI-and Gd-doped samples, which do not strongly depress the superconductivity. These data are discussed considering both phonon and electron thermal conduction mechanisms, and are compared with relevant theories, such as a modified BRT theory of phonon conduction within the superconducting state.