  The orbital and spin magnetization of a cavity-embedded quantum dot array
defined in a GaAs heterostructure are calculated within
quantum-electrodynamical density-functional theory (QEDFT). To this end a
gradient-based exchange-correlation functional recently employed for atomic
systems is adapted to the hosting two-dimensional electron gas (2DEG) submitted
to an external perpendicular homogeneous magnetic field. Numerical results
reveal the polarizing effects of the cavity photon field on the electron charge
distribution and nontrivial changes of the orbital magnetization. We discuss
its intertwined dependence on the electron number in each dot, and on the
electron-photon coupling strength. In particular, the calculated dispersion of
the photon-dressed electron states around the Fermi energy as a function of the
electron-photon coupling strength indicates the formation of
magnetoplasmon-polaritons in the dots.
