极低温热导率探测新型超导体的超导量子态

超导量子态是一种重要的宏观单量子态，对超导量子态的探测和研究，是解决新型超导体的超导配对机制的关键所在。通过极低温热导率测量可以直接探测超导体中的低能准粒子激发，清楚地分辨出超导能隙有没有节点以及是否有大小不同的多个能隙等等，从而获得超导量子态波函数的对称性。我们将利用极低温（至7 mK）、强磁场（至17 T）、旋转磁场（9 T和3 T）等极端实验条件对各种超导体的极低温电、热输运性质进行研究，包括铁基高温超导体、非中心对称超导体、可能的拓扑超导体、重费米子超导体，以及其它新型超导体等，确定它们的超导能隙结构，深入探讨其超导配对机制。

The superconducting state is a very important macroscopic single quantum state. Probing the superconducting state is a key to resolve the superconducting pairing mechanism. By using ultra-low-temperature thermal conductivity measurement, we can directly probe the low-energy quasiparticle excitation in the superconductors, and judge whether there are nodes in the superconducting gap, also whether there are multiple gaps. Therefore we can get the pairing symmetry of the superconducting state wave function. We will use ultra-low-temperature (down to 7 mK), strong magnetic field (up to 17 T), rotating magnetic field (9 T and 3 T) to study the electrical and thermal transport properties of various superconductors, including iron-based superconductors, non-centrosymmetric superconductors, possible topological superconductors, heavy-fermion superconductors, and other new superconductors. We aim to determine their superconducting gap structure, and investigate their superconducting pairing mechanism.