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Massless Boundary Sine-Gordon at the Free Fermion Point: Correlation and Partition Functions with Applications to Quantum Wires

Robert M. Konik
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Abstract

In this report we compute the boundary states (including the boundary entropy) for the boundary sine-Gordon theory. From the boundary states, we derive both correlation and partition functions. Through the partition function, we show that boundary sine-Gordon maps onto a doubled boundary Ising model. With the current-current correlators, we calculate for finite system size the ac-conductance of tunneling quantum wires with dimensionless free conductance 1/2 (or, alternatively interacting quantum Hall edges at filling fraction 1/2). In the dc limit, the results of C. Kane and M. Fisher, Phys. Rev. B46 (1992) 15233, are reproduced.

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Robert M. Konik. 1995-07-09. Massless Boundary Sine-Gordon at the Free Fermion Point: Correlation and Partition Functions with Applications to Quantum Wires. https://arxiv.org/abs/hep-th/9507053

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