SEEBECK AND NERNST EFFECTS IN THE MIXED-STATE OF THE 2-BAND ORGANIC SUPERCONDUCTORS KAPPA-(BEDT-TTF)(2)CU(NCS)(2) AND KAPPA-(BEDT-TTF)(2)CU[N(CN)(2)]BR

The in-plane longitudinal (Seebeck) effect and the transverse (Nernst) effect in magnetic field of the anisotropic superconductors kappa-(BE DT-TTF)(2)Cu(NCS)(2) and kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Br have been s tudied in the vicinity of the superconducting transition. Anomalous si gn changes of the Seebeck as well as of the Nernst voltage were found for the temperature gradient along the direction in which the electron ic transport is dominated by the electron-like carriers. Both effects are attributed to the flux motion under the temperature gradient. The experimental results are interpreted taking into account the anisotrop ic two-band nature of the conducting system in these compounds and ass uming a predominant role of one of the bands (namely, the electron-lik e one) in the superconducting pairing.