||Pump- and Probe-polarization Analyses of Ultrafast Carrier Dynamics in Organic Superconductors
Nakagawa, K. ,
Tsuchiya, S. ,
Yamada, J.Toda, Y.
Journal of superconductivity and novel magnetism
3069 , 2016-12 , Springer
We investigated photo-excited carrier relaxation dynamics in the strongly correlated organic superconductors kappa-(BEDT-TTF)(2)Cu(NCS)(2) and kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Br, using different polarizations of pump and probe pulses. Below the glasslike transition temperature (T (g)) anisotropic responses for probe polarization were observed in both compounds. Decomposing the data into anisotropic and isotropic components, we found the anisotropic component shows no pump polarization dependence, meaning that dissipative excitation process was dominant for the anisotropic carrier relaxation. This behavior indicates that the appearance of anisotropic responses can be associated with spatial symmetry breaking due to structural change of BEDT-TTF molecules.