Peak anomaly of dynamic critical current in NbSe2 crystals

Abstract

We present flow dynamics of vortex matter in the peak effect regime of 2H-NbSe2 crystals investigated by mode locking (ML) and dc transport measurements. Dynamic critical current, characterizing dynamic friction of driven vortices, exhibits a peak behavior against magnetic field and this anomaly occurs above the peak field of the critical current. In fields between these peak behaviors, the ML resonance, characterizing the lattice flow in driven vortices, disappears. The vanishing field of the ML resonance increases with frequency and saturates at high frequency. This saturation behavior will be discussed within a dynamic ordering model and also be compared to the peak anomaly of the dynamic critical current.