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arXiv · 1108.4418

General method for calculating the universal conductance of strongly correlated junctions of multiple quantum wires

Armin Rahmani·Chang-Yu Hou·Adrian Feiguin·Masaki Oshikawa·Claudio Chamon·Ian Affleck
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Abstract

We develop a method to extract the universal conductance of junctions of multiple quantum wires, a property of systems connected to reservoirs, from static ground-state computations in closed finite systems. The method is based on a key relationship, derived within the framework of boundary conformal field theory, between the conductance tensor and certain ground state correlation functions. Our results provide a systematic way of studying quantum transport in the presence of strong electron-electron interactions using efficient numerical techniques such as the standard time-independent density-matrix renormalization-group method. We give a step-by-step recipe for applying the method and present several tests and benchmarks. As an application of the method, we calculate the conductance of the M fixed point of a Y junction of Luttinger liquids for several values of the Luttinger parameter $g$ and conjecture its functional dependence on $g$.

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Armin Rahmani, Chang-Yu Hou, Adrian Feiguin, Masaki Oshikawa, Claudio Chamon, Ian Affleck. 2012-01-28. General method for calculating the universal conductance of strongly correlated junctions of multiple quantum wires. https://doi.org/10.1103/physrevb.85.045120

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