Cavity quantum electrodynamics control of magnetic phases in twisted van der Waals heterostructures

To further increase performance and reduce energy consumption in technological devices, a new paradigm is needed exploiting quantum mechanical phenomena.

An attractive route to enter this paradigm is by interfacing light and magnetic excitations in new optomagnetic devices, which ensures processing frequencies comparable with electronics and hold great promise for future memory, spintronics and quantum computing devices.

This, however, requires a deeper understanding of strongly coupled light-matter systems and the interplay between magnetic, electronic, photonic and lattice excitations.

A promising platform to explore exotic magnetic phenomena is magnetic van der Waals (vdW) materials, since the competition of anisotropy, quantum fluctuations and spin-orbit coupling make these materials prime candidates to host such states and susceptible to material engineering techniques. This can be exploited in cavity quantum electrodynamics (c-QED) and Moiré engineering to control the magnetic state.

By combining c-QED with Moiré engineering, the goal of CavityMag is to construct schemes to control the magnetic state of vdW materials and to induce exotic magnetic phases.

This will be achieved by developing state-of-the-art computational tools based on quantum electrodynamical density functional theory (QED-DFT) in combination with effective spin-photon models.

This computational framework will be used to perform a systematic study of light-induced magnetic phases in twisted vdW materials, to gain a deeper understanding of how microscopic magnetic interactions can be modified, and to establish concrete protocols to control the macroscopic magnetic state.

It will also be used to guide experimental efforts by identifying candidate materials and parameter regimes likely to host exotic states of great promise for the construction of new high performance and energy efficient technological devices.