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arXiv · 1806.06752

Manipulating quantum materials with quantum light

Martin Kiffner·Jonathan Coulthard·Frank Schlawin·Arzhang Ardavan·Dieter Jaksch
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Abstract

We show that the macroscopic magnetic and electronic properties of strongly correlated electron systems can be manipulated by coupling them to a cavity mode. As a paradigmatic example we consider the Fermi-Hubbard model and find that the electron-cavity coupling enhances the magnetic interaction between the electron spins in the ground-state manifold. At half filling this effect can be observed by a change in the magnetic susceptibility. At less than half filling, the cavity introduces a next-nearest neighbour hopping and mediates a long-range electron-electron interaction between distant sites. We study the ground state properties with Tensor Network methods and find that the cavity coupling can induce a new phase characterized by a momentum-space pairing effect for electrons.

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Martin Kiffner, Jonathan Coulthard, Frank Schlawin, Arzhang Ardavan, Dieter Jaksch. 2019-01-25. Manipulating quantum materials with quantum light. https://doi.org/10.1103/physrevb.99.085116

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