A possible glass-like state in theta-(BEDT-TTF)(2)CsZn(SCN)(4) at low temperature
Résumé
We present the results of measurements of conductivity and dielectric permittivity of the quasi-two-dimensional organic salt theta-(BEDT-TTF)(2)CsZn(SCN)(4) along the in- plane direction in a wide temperature range from room temperature down to liquid helium temperature. At temperatures below about 20 K the ac conductivity corresponds to correlated electron motion in disordered systems. Temperature and frequency dependences of the dielectric permittivity exhibit the main features of the slowing down behavior characteristic of various disordered systems. We explain our results by assuming that this low temperature state represents one form of a glass state - a frozen conglomerate of domains of the two q(1) and q(2) short-range charge orders.