Shapiro Steps in NbS3-II at the Temperatures of the Charge-density Wave Transition

The temperature and voltage dependences of conductivity of the monoclinic phase of NbS
₃
are reported. The extremely high coherence of the room-temperature charge-density wave (CDW) allows its synchronization (observation of Shapiro steps) under RF electric field up to T
_P1
=365 K, the temperature of the CDW transition, and even above it. The following regularity is established: the higher is the RF frequency, the higher is the utmost temperature of Shapiro steps observation. Thus, RF field can synchronize CDW fluctuations. The possible contributions of CDW fluctuations to linear and non-linear conductivity are discussed. The result present the NbS
₃
whiskers as high-temperature nano-sized RF detectors.