Photo-induced enhancement of charge density wave current in the quasi-one-dimensional conductor TaS3

In the near vicinity of Peierls transition temperature TP, we have measured the V–I characteristics of the quasi-one-dimensional conductor TaS3 under dark and photo-irradiation conditions. It is found that a significant enhancement of CDW current occurs only around the threshold voltage Vt under photo-irradiation. This effect can be interpreted as a result of screening of pinning potential for CDW condensate by photo-excited quasi-particles (QPʹs). Further the distribution of pinning potential intensity is reflected in the behavior of V–I characteristics near Vt. Our finding suggests that the strength of pinning potential can be controlled by the photo-excited QPʹs in quasi-1D conductors.