Superconductor-insulator transition in disordered Josephson-junction chains
Superconductor-insulator transition in disordered Josephson-junction chains
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DOI：
10.1103/physrevb.96.064514
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发表时间：
2017-08-11
影响因子：
3.7
通讯作者：
Mirlin, A. D.
中科院分区：
文献类型：
--
作者：
Bard, M.;Protopopov, I. V.;Mirlin, A. D.
研究了无序约瑟夫森结链中超导体-绝缘体的量子相变。为此，我们从描述与地(C-0)以及岛(C-1)之间具有电容耦合的超导岛链的晶格模型中推导出场论。我们分析了短距离(C-1和C-0)极限下的理论。向绝缘态的转变是由量子位相滑移的扩散驱动的。最重要的无序来源来自于衬底中的陷阱电荷，这些电荷抑制了相移的一致性，从而有利于超导关联。利用重整化群方法，我们确定了相图，并计算了超导体-绝缘体相变附近直流电导率的温度依赖性和电阻的系统尺寸依赖性。这些依赖关系总体上具有强烈的非单调性，有几个不同的制度反映了超导电性和无序的复杂相互作用。
We study the superconductor-insulator quantum phase transition in disordered Josephson-junction chains. To this end, we derive the field theory from the lattice model that describes a chain of superconducting islands with a capacitive coupling to the ground (C-0) as well as between the islands (C-1). We analyze the theory in the short-range (C-1 > C-0) limits. The transition to the insulating state is driven by the proliferation of quantum phase slips. The most important source of disorder originates from trapped charges in the substrate that suppress the coherence of phase slips, thus favoring superconducting correlations. Using the renormalization-group approach, we determine the phase diagram and evaluate the temperature dependence of the dc conductivity and system-size dependence of the resistance around the superconductor-insulator transition. These dependences have in general strongly nonmonotonic character, with several distinct regimes reflecting an intricate interplay of superconductivity and disorder.