Magneto-optics of layered two-dimensional semiconductors and heterostructures: Progress and prospects

Beginning with the “conventional” two-dimensional (2D) quantum wells based on III–V and II–VI semiconductors in 1970s, to recent atomically thin sheets of van der Waals materials such as 2D semiconducting transition metal dichalcogenides (TMDCs) magnets, research is continuously evolving providing new challenges. Magneto-optical spectroscopy has played a significant role this area research, both from fundamental physics technological perspectives. A major challenge TMDCs understand their spin-valley-resolved implications computation information research. Since discovery valley Zeeman effects, deep insights into spin-valley heterostructures have emerged through magneto-optical spectroscopy. In Perspective, we highlight magneto-optics many milestones interlayer excitons, phase control between coherently excited valleys, determination exciton-reduced masses, Bohr radii binding energies, optically bright dark trions, other many-body species biexcitons phonon replicas TMDC monolayers. The discussion accompanies open questions, challenges, future prospects field including comments involving magnets.