论文标题
RASHBA超导体的螺旋状态的费米表面分割
Fermi surface segmentation in the helical state of a Rashba superconductor
论文作者
论文摘要
我们研究了超导体的FFLO-型螺旋状态下的准颗粒激发，并具有反转对称性断裂和强烈的Rashba自旋轨道耦合。我们局限于在螺旋相中具有库珀对单个有限动量的状态，该状态是由凝结能最小化确定的。我们得出了准粒子分散体对RashBA耦合强度和外场的依赖性。它导致相应的Rashba费米表面表的特殊动量空间分割，但尚未通过实验观察到。我们表明，可以通过准粒子干扰方法直接对其进行可视化，从而识别分段片的临界点，并可以通过场强，偏置电压和RashBA耦合来绘制其演变。我们还指出了一种如何从实验数量中确定有限的库珀对动量的策略。这项研究有可能在Rashba旋转轨道耦合的影响下对螺旋超导状态进行更详细的微观理解。
We investigate the quasiparticle excitations in the FFLO- type helical state of a superconductor with inversion-symmetry breaking and strong Rashba spin-orbit coupling. We restrict to a state with single finite momentum of Cooper pairs in the helical phase that is determined by minimization of the condensation energy. We derive the dependence of quasiparticle dispersions on the Rashba coupling strength and external field. It leads to a peculiar momentum-space segmentation of the corresponding Rashba Fermi surface sheets which has not yet been observed experimentally. We show that it may be directly visualized by the method of quasiparticle interference that identifies the critical points of the segmented sheets and can map their evolution with field strength, bias voltage and Rashba coupling. We also indicate a strategy how to determine the finite Cooper-pair momentum from experimental quantities. This investigation has the potential for a more detailed microscopic understanding of the helical superconducting state under the influence of Rashba spin-orbit coupling.
