Understanding the Quantum Rabi Ring Using Analogies to Quantum Magnetism

Area of Science:

• Quantum Optics
• Condensed Matter Physics
• Quantum Information

Background:

• Quantum Rabi models describe light-matter interactions in coupled cavities.
• Understanding emergent magnetic phenomena in quantum systems is a key challenge.
• Ring cavity geometries offer unique platforms for studying collective quantum effects.

Purpose of the Study:

• To map a quantum Rabi ring model to an effective magnetic model.
• To investigate the phase diagram and emergent phases of the quantum optical system.
• To explore the potential for simulating chiral magnetism using quantum optical platforms.

Main Methods:

• Mapping a quantum Rabi ring (N cavities) to an effective XY and Dzyaloshinskii-Moriya (DM) magnetic model.
• Introducing an artificial magnetic field to modulate photon hopping and induce DM interaction.
• Analyzing the phase diagram for square (N=4) and triangle (N=3) geometries.

Main Results:

• Identified ferro-superradiant, antiferro-superradiant, and chiral superradiant phases in the square geometry.
• The DM interaction is responsible for the chiral phase, analogous to skyrmion magnetizations.
• Geometric frustration in the triangle geometry stabilizes the chiral phase and suppresses the antiferro-superradiant phase.

Conclusions:

• The quantum Rabi ring effectively simulates competing magnetic interactions, including DM interactions.
• Chiral phases exhibit distinct scaling behaviors for odd and even numbers of cavities (N).
• This platform provides a novel approach to simulating and understanding chiral magnetism in few-body quantum systems.