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Nonergodic metallic and insulating phases of Josephson junction chains
Manuel Pino1, Lev B Ioffe2, Boris L Altshuler3
1Department of Physics and Astronomy, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901;
Summary
Conventional statistical physics laws require a heat bath, but new research on Josephson junctions reveals a high-temperature nonergodic phase with finite resistance, challenging these foundations.
Area of Science:
- Statistical Physics
- Quantum Devices
- Condensed Matter Physics
Background:
- Conventional statistical physics relies on heat bath presence and ergodicity.
- Weak coupling to heat baths was assumed sufficient for real systems.
- Recent advances in quantum devices allow study of systems with reduced bath coupling.
Purpose of the Study:
- Revisit the foundations of statistical mechanics for systems with weak heat bath coupling.
- Investigate the behavior of Josephson junction chains under these conditions.
- Identify novel phases and properties in reduced-bath-coupling systems.
Main Methods:
- Theoretical examination of Josephson junction chains.
- Analysis of systems with dramatically reduced coupling to a heat bath.
- Investigating high-temperature nonergodic phases.
Main Results:
- A Josephson junction chain exhibits a novel high-temperature nonergodic phase with finite resistance.
- At higher temperatures, the system transitions to a fully localized state.
- This localized state is characterized by infinite resistance and long relaxation times.
Conclusions:
- The study challenges the universal applicability of conventional statistical mechanics.
- Novel nonergodic phases can emerge in systems with weak heat bath coupling.
- Josephson junction chains serve as a model system for exploring these phenomena.
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