A systematic study of femtosecond quasiparticle relaxation processes in La2-xSrxCuO4 -: art. no. 014544

A systematic study of quasiparticle recombination and relaxation dynamics in La2-xSrxCuO4 for x=0.06, 0.1, 0.115, 0.15, and 0.2 unambiguously shows the presence of two distinct components in the relaxation, one being present only below T-c while the other vanishes at much higher temperatures. The two components are attributed to the intrinsically inhomogeneous ground state in cuprates. Since there are no charge reservoirs in the 2-1-4 system, the presence of two components can only be attributed to inhomogeneity of the CuO2 planes.