Mean Field Theory for Underdamped Josephson Junction Arrays with an Offset Voltage

Abstract

We study a model Hamiltonian for superconductivity in underdamped Josephson junction arrays in the presence of an offset voltage between the array and the substrate. We develop an approximate zero-temperature (T = 0) phase diagram as a function of Josephson coupling, charging energy, and offset voltage, using a simple Hartree-type mean-field approximation. With diagonal charging energy, the calculated phase diagram is periodic in offset voltage, in agreement with previous results. At a special value of this voltage such that states with n and n+1 Cooper pairs per grain are degenerate, only an infinitesimal Josephson coupling is needed to establish long-range phase coherence in this approximation. With both diagonal and nearest-neighbor charging energies, the T = 0 phase diagram has two types of insulating lobes with different kinds of charge order, and two types of superconducting regions. One of these is a ``supersolid'' in which long-range phase coherence coexists with a frozen charge density wave. We briefly discuss connections to previous calculations, and possible relevance to experiments.

13 pages, LaTex file,6 figures appended in postscript

Cited by in corpus (29)

• Quantum phases in an optical lattice
• Quantum Phase Transitions and Vortex Dynamics in Superconducting Networks
• Supersolid hardcore bosons on the triangular lattice
• Phase separation in supersolids
• Supersolids versus phase separation in two-dimensional lattice bosons
• Magnetization plateaus of the Shastry-Sutherland model for SrCu_2(BO_3)_2: SDW, supersolid and bound states
• Superfluids and Supersolids on Frustrated 2D Lattices
• Quantum-Phase Transitions of Interacting Bosons and the Supersolid Phase
• Simultaneous Diagonal and Off Diagonal Order in the Bose--Hubbard Hamiltonian
• On the Coexistence of Diagonal and off-Diagonal Long-Range Order, a Monte Carlo Study
• The Bose Metal: gauge field fluctuations and scaling for field tuned quantum phase transitions
• Phase Diagram of Interacting Bosons on the Honeycomb Lattice
• Critical Behavior of the Supersolid transition in Bose-Hubbard Models
• Strong-coupling perturbation theory for the two-dimensional Bose-Hubbard model in a magnetic field
• Inelastic light scattering from a Mott insulator
• Critical properties of two-dimensional Josephson junction arrays with zero-point quantum fluctuations
• Phase diagrams, critical and multicritical behavior of hard-core Bose-Hubbard models
• Quantum phase transition with dissipative frustration
• Mean Field Theory of Josephson Junction Arrays with Charge Frustration
• Ring Exchange and Phase Separation in the Two-dimensional Boson Hubbard model
• One-dimensional Josephson arrays as superlattices for single Cooper pairs
• Effects of dissipation on the superfluid-Mott-insulator transition of photons
• Ground state properties of charge and magnetically frustrated two--dimensional quantum Josephson--junction arrays
• First Order Superconductor to Insulator Transition: Evidence for a Supersolid Phase
• Supersolid phase in fully frustrated Josephson junction arrays
• Renormalization-group study of gate charge effects in Josephson-junction chains
• Dimensional crossover in self-organised super-radiant phases of ultra cold atoms inside a cavity
• Phase and Charge reentrant phase transitions in two capacitively coupled Josephson arrays with ultra-small junction
• Phase diagram of 2D array of mesoscopic granules