YBa_2Cu_3O_(7-δ)反常比热的研究

An Study on Abnormal Specific Heat of YBa_2Cu_3O_(7-δ)

该文对不同热处理条件制备的YBa_2Cu_3O_(7-σ)样品,在70～273K温区内,用扫描法进行了比热容测量。结果表明:除了在91K附近其比热容有正跃变外,在100～180K温区内尚有多个反常的负的跃变。而且这些反常跃变与样品的热处理条件及测量前样品所处的温度有关.

In the temperature range of 70~273K,scanning method of the measurement on specific heat is used to study the YBa2Cu3O7-δ superconductor samples made by different thermal treatment conditions.The results of present work indicate that:except for the normal positive transitions of specific heat at their critical temperature,about 91K,there are several negative transitions in the temperature range of 100~180.K,Moreover,these abnormal transitions of specific heat are not only related to the thermal treatment conditions but also to the different temperatures at which the measurements are started.