Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit
Riya Sett, Farid Hassani, Duc Phan, Shabir Barzanjeh, Andras Vukics, Johannes M. Fink
DOI 10.1103/PRXQuantum.5.010327 · PRX Quantum
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
The photon blockade breakdown in a continuously driven cavity QED system has been proposed as a prime example for a first-order driven-dissipative quantum phase transition. However, the predicted scaling from a microscopic behavior—dominated by quantum fluctuations—to a macroscopic one—characterized by stable phases—and the associated exponents and phase diagram have not been observed so far. In this work we couple a single transmon qubit with a fixed coupling strength g to a superconducting cavity that is in situ bandwidth κ tunable to controllably approach this thermodynamic limit. Even though the system remains microscopic, we observe its behavior becoming increasingly macroscopic as a function of g/κ. For the highest realized g/κ of approximately 287, the system switches with a characteristic timescale as long as 6 s between a bright coherent state with approximately 8×103 intracavity photons and the vacuum state. This exceeds the microscopic timescales by 6 orders of magnitude and approaches the perfect hysteresis expected between two macroscopic attractors in the thermodynamic limit. These findings and interpretation are qualitatively supported by neoclassical theory and large-scale quantum-jump Monte Carlo simulations. Besides shedding more light on driven-dissipative physics in the limit of strong light-matter coupling, this system might also find applications in quantum sensing and metrology.
Similar papers
Prospects for Strong Cavity Quantum Electrodynamics with Superconducting Circuits
similarity 0.90S. M. Girvin et al. · 2003 · arXiv:cond-mat/0310670
Source status unknown — claims are unverified
Observation of the photon-blockade breakdown phase transition
similarity 0.88Fink, J. M. et al. · 2017 · arXiv:1607.04892
Source status unknown — claims are unverified
Coexistence of Nonequilibrium Density and Equilibrium Energy Distribution of Quasiparticles in a Superconducting Qubit
similarity 0.88Thomas Connolly et al.
Source status unknown — claims are unverified
Cavity QED in superconducting circuits: susceptibility at elevated temperatures
similarity 0.88Ileana Rau et al. · 2004 · arXiv:cond-mat/0403257
Source status unknown — claims are unverified
Measurement-Induced State Transitions in a Superconducting Qubit: Beyond the Rotating Wave Approximation
similarity 0.88Daniel Sank et al.
Source status unknown — claims are unverified
Dynamics of nonequilibrium quasiparticles in narrow-gap superconducting tunnel junctions
similarity 0.86A. G. Kozorezov et al.
Source status unknown — claims are unverified