Strong Temperature Variation of Radio Frequency Noise Emission from Josephson Point Contact

Abstract

The temperature dependence of radio frequency noise emission from the Nb–Nb superconducting point contact near the critical current is investigated. An anomalous temperature dependence of the RF emission intensity is observed above 7 K; a dip in the RF emission intensity is observed above 8 K. Strong temperature variation of the RF resistance associated with an anomaly in the cosφ term of the Josephson junction is considered to be one of the possible origin for the decrease of the emission intensity near the critical temperature.