Cavity-renormalized quantum criticality in a honeycomb bilayer antiferromagnet

RWTH Publications (RWTH Aachen)

Abstract

Strong light-matter interactions as realized in an optical cavity provide a tantalizing opportunity to control the properties of condensed matter systems. Inspired by experimental advances in cavity quantum electrodynamics and the fabrication and control of two-dimensional magnets, we investigate the fate of a quantum critical antiferromagnet coupled to an optical cavity field. Using unbiased quantum Monte Carlo simulations, we compute the scaling behavior of the magnetic structure factor and other observables. While the position and universality class are not changed by a single cavity mode, the critical fluctuations themselves obtain a sizable enhancement, scaling with a fractional exponent that defies expectations based on simple perturbation theory. The scaling exponent can be understood using a generic scaling argument, based on which we predict that the effect may be even stronger in other universality classes. Our microscopic model is based on realistic parameters for two-dimensional magnetic quantum materials and the effect may be within the range of experimental detection.

Authors 5

1. Lukas Weber

   Flatiron Institute · Max Planck Institute for the Structure and Dynamics of Matter

   Affiliation as printed

   Center for Computational Quantum Physics , The Flatiron Institute , 162 Fifth Avenue , New York , New York 10010 , USA

   Max Planck Institute for the Structure and Dynamics of Matter , Luruper Chaussee 149 , 22761 Hamburg , Germany

   Center for Computational Quantum Physics, The Flatiron Institute, 162 Fifth Avenue, New York, New York 10010, USA

   Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany

2. Emil Viñas Boström

   Max Planck Institute for the Structure and Dynamics of Matter

   Affiliation as printed

   Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany

3. Martin Claassen

   University of Pennsylvania

   Affiliation as printed

   Department of Physics and Astronomy , University of Pennsylvania , Philadelphia , PA 19104 , USA

   Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA

4. Ángel Rubio

   Flatiron Institute · Max Planck Institute for the Structure and Dynamics of Matter

   Affiliation as printed

   Center for Computational Quantum Physics , The Flatiron Institute , 162 Fifth Avenue , New York , New York 10010 , USA

   Max Planck Institute for the Structure and Dynamics of Matter , Luruper Chaussee 149 , 22761 Hamburg , Germany

   Center for Computational Quantum Physics, The Flatiron Institute, 162 Fifth Avenue, New York, New York 10010, USA

   Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany

5. Dante Marvin Kennes Aachen Institute for Theoretical Solid State Physics

   RWTH Aachen University · Jülich Aachen Research Alliance · Max Planck Institute for the Structure and Dynamics of Matter

   Affiliation as printed

   Institute for Theoretical Solid State Physics, RWTH Aachen University, 52062 Aachen, Germany

   JARA-Fundamentals of Future Information Technology, Jülich, Germany

   Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany