Thermal transport in a Luttinger liquid

We study thermal transport in a one-dimensional (1D) interacting electron gas, employing the Luttinger liquid model. Both thermal conductance and thermopower are analyzed for a pure 1D gas and with impurities. The universal ratio of electrical to thermal conductance in a Fermi liquid-the Wiedemann-Franz law-is modified, whereas the thermopower is still linear in temperature. For a single impurity the Lorentz number is given by L(T --> 0) = 3L(0)/(2g + g(2))-with L(0) the Fermi liquid value-and the conductance 1/2 < g < 1. For g < 1/2 the Lorentz number diverges as T --> 0. Possible relevance to thermal transport in conducting polymer systems is discussed.