Quantum fluctuations and dissipative phase transition in one-dimensional Josephson junction arrays

Abstract

We studied superconductor–insulator transition in one-dimensional arrays of small Josephson junctions in which each junction was shunted by ohmic resistor. The I– V characteristics changed from Coulomb-blockade type behavior to Josephson-like one with decreasing shunt resistance R S, even when the Josephson coupling energy E J was much smaller than the charging energy E C (≡e 2/C , C : junction capacitance ) . The critical value of R S was close to R Q (≡6.45 kΩ) for E J/ E C smaller than unity. This agrees with theoretical predictions for dissipation-driven phase transitions in this system.