arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2305.06015cond-mat.supr-con
收藏

附着铁磁团簇的超导薄膜中的 Fulde-Ferrell-Larkin-Ovchinnikov 态

Fulde-Ferrell-Larkin-Ovchinnikov state in a superconducting thin film attached to a ferromagnetic cluster

Shu-Ichiro Suzuki, Takumi Sato, Alexander A. Golubov, Yasuhiro Asano

AI总结:

本文通过二维求解 Eilenberger 方程,研究附着圆形铁磁团簇的超导薄膜中的局域 FFLO 态,揭示节点、稳定机制、奇频 $p$ 波配对及亚能隙谱特征。

摘要:

我们从理论上研究了在带有小型圆形磁性团簇的超导薄膜中局域出现的 Fulde-Ferrell-Larkin-Ovchinnikov(FFLO)态。通过在二维中求解 Eilenberger 方程,我们针对若干团簇尺寸和交换势计算了配对势、配对关联、自由能密度和准粒子态密度。配对势中节点的数量随交换势和团簇尺寸的增大而增加。即使铁磁体下方的自由能密度在局域上超过正常态数值,远离磁性团簇的超导凝聚体仍会使局域 FFLO 态稳定。对配对关联函数的分析表明,自旋单重态 $s$ 波配对势的空间变化会产生 $p$ 波 Cooper 对,并且奇频 Cooper 对支配着局域态密度中的非均匀亚能隙谱。我们还基于所计算的准粒子态密度讨论了一种探测局域 FFLO 态的方法。

英文摘要:

We study theoretically the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) states appearing locally in a superconducting thin film with a small circular magnetic cluster. The pair potential, the pairing correlations, the free-energy density, and the quasiparticle density of states are calculated for several cluster sizes and the exchange potentials by solving the Eilenberger equation in two dimensions. The number of nodes in the pair potential increases with increasing the exchange potential and cluster size. The local FFLO states are stabilized by the superconducting condensate away from the magnetic cluster even though the free-energy density beneath the ferromagnet exceeds locally the normal-state value. The analysis of the pairing-correlation functions shows that the spatial variation of the spin-singlet $s$-wave pair potential generates $p$-wave Cooper pairs, and that odd-frequency Cooper pairs govern the inhomogeneous subgap spectra in the local density of states. We also discuss a way of detecting the local FFLO states based on the calculated quasiparticle density of states.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑