We present a theory predicting how the linear magnetotransport of a two-dimensional (2D) electron gas is modified by a passive electromagnetic cavity resonator where no real photons are injected nor created. For a cavity photon mode with in-plane linear polarization, the dc bulk magnetoresistivity of the 2D electron gas is anisotropic. In the regime of high filling factors of the Landau levels, the envelope of the Shubnikov–de Haas oscillations is profoundly modified and the resistivity can be increased or reduced depending on the system parameters. In the limit of low magnetic fields, the resistivity along the cavity-mode polarization direction is enhanced in the ultrastrong light-matter coupling regime. Our work shows the crucial role of virtual polariton excitations in controlling the dc charge transport properties of cavity-embedded systems.

• Received 7 May 2018
• Revised 11 October 2018

DOI:https://doi.org/10.1103/PhysRevB.98.205301