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arXiv · 0708.1850

Transport Properties of a spinon Fermi surface coupled to a U(1) gauge field

Cody P. Nave·Patrick A. Lee
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Abstract

With the organic compound $κ$-(BEDT-TTF)$_2$-Cu$_2$(CN)$_3$ in mind, we consider a spin liquid system where a spinon Fermi surface is coupled to a U(1) gauge field. Using the non-equilibrium Green's function formalism, we derive the Quantum Boltzmann Equation (QBE) for this system. In this system, however, one cannot a priori assume the existence of Landau quasiparticles. We show that even without this assumption one can still derive a linearized equation for a generalized distribution function. We show that the divergence of the effective mass and of the finite temperature self-energy do not enter these transport coefficients and thus they are well-defined. Moreover, using a variational method, we calculate the temperature dependence of the spin resistivity and thermal conductivity of this system.

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Cody P. Nave, Patrick A. Lee. 2007-08-14. Transport Properties of a spinon Fermi surface coupled to a U(1) gauge field. https://doi.org/10.1103/physrevb.76.235124

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