Golubev Dmitri S, Kalenkov Mikhail S, Zaikin Andrei D
Forschungszentrum Karlsruhe, Institut für Nanotechnologie, 76021 Karlsruhe, Germany.
Phys Rev Lett. 2009 Aug 7;103(6):067006. doi: 10.1103/PhysRevLett.103.067006. Epub 2009 Aug 6.
We formulate a microscopic theory of nonlocal electron transport in three-terminal diffusive normal-superconducting-normal (NSN) structures with arbitrary interface transmissions. At low energies epsilon, we predict strong enhancement of nonlocal spectral conductance g_{12} proportional, variant1/epsilon due to quantum interference of electrons in disordered N terminals. In contrast, nonlocal resistance R_{12} remains smooth at small epsilon and, furthermore, is found to depend neither on parameters of normal-superconducting interfaces nor on those of N terminals. At higher temperatures, R_{12} exhibits a peak caused by the trade-off between charge imbalance and Andreev reflection. Our results are in a good agreement with recent experimental observations and can be used for quantitative analysis of future experiments.
我们构建了一个关于具有任意界面透射率的三端扩散型正常 - 超导 - 正常（NSN）结构中非局域电子输运的微观理论。在低能量ε下，我们预测由于无序N端中电子的量子干涉，非局域光谱电导g₁₂会有强烈增强，与1/ε成正比。相比之下，非局域电阻R₁₂在小ε时保持平滑，并且进一步发现它既不依赖于正常 - 超导界面的参数，也不依赖于N端的参数。在较高温度下，R₁₂表现出由电荷不平衡和安德列夫反射之间的权衡引起的一个峰值。我们的结果与最近的实验观测结果非常吻合，可用于未来实验的定量分析。
