Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:quant-ph/0403185 · Physical Review Letters

First-Order Superradiant Phase Transitions in a Multiqubit Cavity System

Chiu Fan Lee, Neil F. Johnson

Published Aug 18, 2004• 65 citations
arXivHTMLPDF

Abstract

We predict the existence of novel first-order phase transitions in a general class of multiqubit cavity systems. Apart from atomic systems, the associated superradiant phase transition should be observable in a variety of solid-state experimental systems, including the technologically important case of interacting quantum dots coupled to an optical cavity mode.

DOI
10.1103/physrevlett.93.083001

Related papers

Exploring super-radiant phase transitions via coherent control of a multi-qubit--cavity system

Timothy Jarrett, Chiu Fan Lee, Neil F. Johnson

We propose the use of coherent control of a multi-qubit--cavity QED system in order to explore novel phase transition phenomena in a general class of multi-qubit--cavity systems. In addition to atomic systems, the associated super-radiant phase transitions should be observable in a variety of solid-state experimental systems, including the technologically important case of interacting quantum dots coupled to an optical cavity mode.

arXiv:quant-ph/0503015•Mar 1, 2005•0 citations

Quantum phase transitions in coupled two-level atoms in a single-mode cavity

Qing‐Hu Chen, Tao Liu, Yuyu Zhang +1 more

The dipole-coupled two-level atoms (qubits) in a single-mode resonant cavity are studied by extended bosonic coherent states. The numerical solution is presented. The first-order quantum phase transitions may occur in finite systems, in contrast to the original Dicke model. This system also exhibits a second-order quantum phase transition from the normal to the superradiant phase, as in the original Dicke model. Finite-size scaling for several observables---such as average fidelity susceptibility, order parameter, and concurrence---is performed for different interatomic interactions. The scaling exponents obtained suggest that interatomic interactions do not change the universality class.

arXiv:1008.1093•Physical Review A•Nov 30, 2010•28 citations

Quantum phase transitions of the Bose-Hubbard model inside a cavity

Yu Chen, Zhenhua Yu, Hui Zhai

The superfluid to Mott insulator transition and the superradiant transition are textbook examples of quantum phase transition and coherent quantum optics, respectively. Recent experiments in ETH and Hamburg have succeeded in loading degenerate bosonic atomic gases in optical lattices inside a cavity, which enables the first experimental study of the interplay between these two transitions. In this Rapid Communication we present the theoretical phase diagram for the ETH Zurich experimental setup, and determine the phase boundaries and the orders of the phase transitions between the normal superfluid phase, the superfluid with superradiant light, the normal Mott insulator, and the Mott insulator with superradiant light. We find that in contrast to the second-order superradiant transition in a weakly interacting Bose condensate, strong correlations in the superfluid nearby a Mott transition can render the superradiant transition to a first-order one. Our results will stimulate further experimental studies of interactions between cavity light and strongly interacting quantum matter.

arXiv:1602.02478•Physical Review A•Apr 13, 2016•65 citations

Phase-driven unconventional superradiance phase transition in non-Hermitian cascaded quantum Rabi cavities

Shujie Cheng, Shuai-Peng Wang, G. D. de Moraes Neto +1 more

This study investigates phase-driven symmetry breaking leading to superradiance phase transitions in cascaded non-Hermitian quantum Rabi cavities. Non-Hermiticity is introduced via the phase coupling $\ensuremath{\varphi}$ between the atom and the optical field. In the thermodynamic limit of the quantum harmonic oscillator, we analytically derive the superradiance phase boundary, validated by observables. An unconventional quantum phase transition without a Hermitian analog arises when $|\ensuremath{\varphi}|=\frac{\ensuremath{\pi}}{4}$ or $\frac{3\ensuremath{\pi}}{4}$, where the phase boundary is uniquely determined by the cavity coupling, at $\mathcal{J}=\frac{1}{2}$ ($\mathcal{J}$ is the ratio of the cavity coupling strength $J$ to the optical field frequency ${\ensuremath{\omega}}_{p}$, and $\mathcal{J}=\frac{J}{{\ensuremath{\omega}}_{p}}$), independent of the atom-photon coupling strength $g$. For other $\ensuremath{\varphi}$, the phase boundary relies on both $\mathcal{J}$ and $g$, similar to the scenario observed in Hermitian systems. Furthermore, we identify phase-driven first- and second-order superradiance phase transitions, focusing on the quantum criticality of the second-order transition by determining the critical exponents and the universality class. The feasibility of experimental realization is also discussed, aiming to inspire further studies on non-Hermitian superradiance quantum phase transitions.

arXiv:2406.16576•Physical Review A•May 1, 2025•3 citations

Optically controlled spin glasses in multiqubit cavity systems

Timothy Jarrett, Chiu Fan Lee, Neil F. Johnson

Recent advances in nanostructure fabrication and optical control suggest that it will soon be possible to prepare collections of interacting two-level systems (i.e., qubits) within an optical cavity. Here we show theoretically that such systems could exhibit phase transition phenomena involving spin-glass phases. By contrast with traditional realizations using magnetic solids, these phase transition phenomena are associated with both matter and radiation subsystems. Moreover the various phase transitions should be tunable simply by varying the matter-radiation coupling strength.

arXiv:cond-mat/0604623•Physical Review B•Sep 6, 2006•13 citations

Superradiant phase transition with cavity-assisted dynamical spin-orbit coupling

Ying Lei, Shaoliang Zhang

The superradiant phase transition represents an important quantum phenomenon that shows collective excitations based on the coupling between atoms and cavity modes. Spin-orbit coupling is another quantum effect which is induced by the interaction of the atomic internal degrees of freedom and center-of-mass momentum. In this work we consider the cavity-assisted dynamical spin-orbit coupling which comes from the combination of these two effects. It can generate a series of interesting quantum phenomena such as the flat spectrum and the discontinuity of the excitation energy spectrum around the critical point of the quantum phase transition. We further discuss the influence of atom decay and nonlinear coupling on the phase diagram. The atom decay suppresses the discontinuity of the phase diagram and the nonlinear coupling can break the symmetric properties of the phase transition. Our work provides a theoretical method to research the rich quantum phenomena in this dynamic many-body system.

arXiv:2012.10098•Physical Review A•May 21, 2021•2 citations
We predict the existence of novel first-order phase transitions in a general class of multiqubit cavity systems. Apart from atomic systems, the associated superradiant phase transition should be observable in a variety of solid-state experimental systems, including the technologically important case of interacting quantum dots coupled to an optical cavity mode.
The dipole-coupled two-level atoms (qubits) in a single-mode resonant cavity are studied by extended bosonic coherent states. The numerical solution is presented. The first-order quantum phase transitions may occur in finite systems, in contrast to the original Dicke model. This system also exhibits a second-order quantum phase transition from the normal to the superradiant phase, as in the original Dicke model. Finite-size scaling for several observables---such as average fidelity susceptibility, order parameter, and concurrence---is performed for different interatomic interactions. The scaling exponents obtained suggest that interatomic interactions do not change the universality class.
The superfluid to Mott insulator transition and the superradiant transition are textbook examples of quantum phase transition and coherent quantum optics, respectively. Recent experiments in ETH and Hamburg have succeeded in loading degenerate bosonic atomic gases in optical lattices inside a cavity, which enables the first experimental study of the interplay between these two transitions. In this Rapid Communication we present the theoretical phase diagram for the ETH Zurich experimental setup, and determine the phase boundaries and the orders of the phase transitions between the normal superfluid phase, the superfluid with superradiant light, the normal Mott insulator, and the Mott insulator with superradiant light. We find that in contrast to the second-order superradiant transition in a weakly interacting Bose condensate, strong correlations in the superfluid nearby a Mott transition can render the superradiant transition to a first-order one. Our results will stimulate further experimental studies of interactions between cavity light and strongly interacting quantum matter.
This study investigates phase-driven symmetry breaking leading to superradiance phase transitions in cascaded non-Hermitian quantum Rabi cavities. Non-Hermiticity is introduced via the phase coupling $\ensuremath{\varphi}$ between the atom and the optical field. In the thermodynamic limit of the quantum harmonic oscillator, we analytically derive the superradiance phase boundary, validated by observables. An unconventional quantum phase transition without a Hermitian analog arises when $|\ensuremath{\varphi}|=\frac{\ensuremath{\pi}}{4}$ or $\frac{3\ensuremath{\pi}}{4}$, where the phase boundary is uniquely determined by the cavity coupling, at J=12\mathcal{J}=\frac{1}{2}J=21​ (J\mathcal{J}J is the ratio of the cavity coupling strength JJJ to the optical field frequency ${\ensuremath{\omega}}_{p}$, and $\mathcal{J}=\frac{J}{{\ensuremath{\omega}}_{p}}$), independent of the atom-photon coupling strength ggg. For other $\ensuremath{\varphi}$, the phase boundary relies on both J\mathcal{J}J and ggg, similar to the scenario observed in Hermitian systems. Furthermore, we identify phase-driven first- and second-order superradiance phase transitions, focusing on the quantum criticality of the second-order transition by determining the critical exponents and the universality class. The feasibility of experimental realization is also discussed, aiming to inspire further studies on non-Hermitian superradiance quantum phase transitions.
Recent advances in nanostructure fabrication and optical control suggest that it will soon be possible to prepare collections of interacting two-level systems (i.e., qubits) within an optical cavity. Here we show theoretically that such systems could exhibit phase transition phenomena involving spin-glass phases. By contrast with traditional realizations using magnetic solids, these phase transition phenomena are associated with both matter and radiation subsystems. Moreover the various phase transitions should be tunable simply by varying the matter-radiation coupling strength.
The superradiant phase transition represents an important quantum phenomenon that shows collective excitations based on the coupling between atoms and cavity modes. Spin-orbit coupling is another quantum effect which is induced by the interaction of the atomic internal degrees of freedom and center-of-mass momentum. In this work we consider the cavity-assisted dynamical spin-orbit coupling which comes from the combination of these two effects. It can generate a series of interesting quantum phenomena such as the flat spectrum and the discontinuity of the excitation energy spectrum around the critical point of the quantum phase transition. We further discuss the influence of atom decay and nonlinear coupling on the phase diagram. The atom decay suppresses the discontinuity of the phase diagram and the nonlinear coupling can break the symmetric properties of the phase transition. Our work provides a theoretical method to research the rich quantum phenomena in this dynamic many-body system.