铜氧化物超导体中赝能隙及相关物理性质的研究

对于普通的低温超导体，在超导转变温度之下存在一个超导能隙，而这个超导能隙则反映了在超导态时形成电子库柏对的配对强度。与普通的低温超导体不同，铜氧化物高温超导体除了在超导转变温度之下存在一个超导能隙之外，在超导转变温度之上和一个特定的温度之下，还存在一个正常态赝能隙，而对应的这个特定温度则称之为正常态赝能隙的跨接温度。经过20余年的艰苦努力，人们发现铜氧化物高温超导体中正常态赝能隙的存在是最为惊奇的物理现象，而且这个正常态赝能隙与铜氧化物高温超导体中的一系列反常物理性质密切相关。我们在动能驱动的高温超导电性机理框架下并通过考虑正常态赝能隙与超导能隙之间的相互关系统一探讨铜氧化物高温超导体中与正常态赝能隙密切相关并从正常态到超导态演化的一系列重要物理性质，为铜氧化物高温超导体中出现的这些反常物理现象提供一个整体的微观物理说明。

In conventional superconductors, a superconducting gap exists in the energy spectrum only below the superconducting transition temperature corresponding to the price to pay in energy for breaking a Cooper pair of electrons and creating two excited states. However, in cuprate superconductors above the superconducting transition temperature but below a special temperature, an energy gap called the normal-state pseudogap exists, while this special temperature is called as the normal-state pseudogap crossover temperature. After intensive investigations over more than two decades, it has become clear that the interplay between the superconducting gap and normal-state pseudogap is the mostly remarkable effect, and this normal-state pseudogap is closely related to the superconducting mechanism and anomalous properties in cuprate superconductors. Within the kinetic energy driven superconducting mechanism, we study the unusual physical properties in cuprate superconductors by considering the interplay between the superconducting gap and normal-state pseudogap.