Quantum Phase Transitions and Particle-Hole Pair Transport in Capacitively Coupled Josephson-Junction Chains

Mahn-Soo Choi; M. Y. Choi; Sung-Ik Lee

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Quantum Phase Transitions and Particle-Hole Pair Transport in Capacitively Coupled Josephson-Junction Chains

Mahn-Soo Choi·M. Y. Choi·Sung-Ik Lee

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Abstract

We consider two chains of ultrasmall Josephson junctions, coupled capacitively with each other, and investigate the transport of particle-hole pairs and the quantum phase transitions at zero temperature. For appropriate parameter ranges, the particle-hole pairs are found to play major roles in transport phenomena; condensation of such pairs leads to the superconducting state, displaying perfect drag of supercurrents along the two chains.

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Mahn-Soo Choi, M. Y. Choi, Sung-Ik Lee. 1998-02-19. Quantum Phase Transitions and Particle-Hole Pair Transport in Capacitively Coupled Josephson-Junction Chains. https://arxiv.org/abs/cond-mat/9802199

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