Thermoelectric and thermal transport properties in ABA-stacked trilayer graphene

We numerically study the thermoelectric and thermal transport in ABA-stacked trilayer graphene in the presence of a strong magnetic field and disorder. We find that the thermoelectric conductivities display different asymptotic behaviors, depending on the ratio between the temperature and the width of the disorder-broadened Landau levels (LLs), similar to those of monolayer graphene. In the high temperature regime, the transverse thermoelectric conductivity α <Subscript> xy </Subscript> saturates to a universal value 8.31k <Subscript> B </Subscript> e / h at the center of each LL, and displays a linear temperature dependence at low temperatures. The calculated Nernst signal has a peak with a height of the order of k <Subscript> B </Subscript> / e, while the thermopower changes sign at the central LL. We attribute this unique behavior at the central is due to the coexistence of particle and hole LLs. We further study the thermal transport from electronic origin and verify the validity of the generalized Weidemann-Franz law. Copyright EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2012