Nonequilibrium transitions in fully frustrated Josephson junction arrays

Area of Science:

• Condensed matter physics
• Quantum mechanics
• Superconductivity

Background:

• Josephson junction arrays exhibit complex behaviors influenced by thermal fluctuations.
• Understanding symmetry breaking is crucial for characterizing emergent phenomena in condensed matter systems.

Purpose of the Study:

• To investigate the impact of thermal fluctuations on symmetry breaking in a driven Josephson junction array.
• To determine the critical temperatures for Z2 and U(1) symmetry transitions.

Main Methods:

• Numerical calculations of the chiral order parameter and transverse helicity modulus.
• Analysis of system behavior as a function of temperature under current drive.

Main Results:

• The Z2 symmetry transition temperature T(Z2)(I) was found to be lower than the U(1) symmetry transition temperature T(U(1))(I).
• Both transitions were identified as experimentally observable through longitudinal and transverse voltage measurements.

Conclusions:

• Thermal fluctuations lead to distinct transition temperatures for different symmetries in Josephson junction arrays.
• Experimental observation of these transitions provides a method for probing the underlying physics of frustrated superconducting systems.