Perspective on the physics of two-dimensional perovskites in high magnetic field

Two-dimensional (2D) metal halide perovskites consist of atomically thin layers composed of low bandgap metal-halide slabs, surrounded by high bandgap organic ligands, which behave as barriers. In this Perspective, we highlight how the use of large magnetic fields has been an extremely insightful tool to unravel some of the fundamental electronic properties of 2D perovskites. We focus on the combination of magnetoabsorption measurements and theoretical modeling to extract the carrier effective mass, on the use of magnetic field to clarify the fine structure of the exciton manifold, and on how magnetic fields can be helpful to correctly assign side peaks in the complex absorption or photoluminescence spectra displayed by 2D perovskites. We finally point out some challenges which might be successfully addressed by magneto-optical experimental techniques.