The incommensurate spin density wave (SDW) phases in (TMTSF)2PF6 and (TMTTF)2Br were investigated by transport measurements under pressure and in magnetic field parallel to the c*-axis. For the SDW phase of (TMTSF)2PF6 slightly suppressed by the pressure, the SDW transition temperature TSDW increases with the applied magnetic field. The field dependence of TSDW is described by a quadratic behavior and the coefficient of the quadratic term increases with increasing pressure. For the incommensurate SDW phase of (TMTTF)2Br stabilized under the pressure above 0.5 GPa, the SDW transition shows similar behavior as in the case of (TMTSF)2PF6 with increasing magnetic field. These results are consistent with the prediction of the mean field theory based on the nesting of the Fermi surface. The incommensurate SDW phases in both (TMTSF)2PF6 and (TMTTF)2Br are understood in a common pressure axis with taking the reduction of the coupling constant by the pressure into account.
|Number of pages||10|
|Journal||Physica Status Solidi (B): Basic Research|
|Publication status||Published - 2001 Jan|