Quantum fluctuations in chains of Josephson junctions

摘要: We study the effect of quantum fluctuations phase on low-temperature behavior two models Josephson junction chains with Coulomb interactions taken into account. The first model, which represents a chain junctions close to ground plane, is Hamiltonian version two-dimensional XY model in one space and time dimension. demonstrate explicitly how Nelson-Kosterlitz jump manifests itself conduction properties this system at critical value superconducting grain capacitance. In second charging energy for single just parallel-plate capacitor Q/sup 2//8C, where Q charge difference across C its show that any nonzero (i.e.,