Moir’e trapped interlayer excitons (IXs) in heterobilayer transition metal dichalcogenides currently attract strong interest due to their potential for non-classical light generation, coherent spin-photon interfaces and exploring novel correlated phases of electrons. Here, we report lasing of moir’e trapped IXs by integrating a pristine hBN-encapsulated MoSe$_2$/WSe$_2$ heterobilayer in a high-Q ($>10^4$) nanophotonic cavity. We control the detuning between the IX line and the cavity mode with a magnetic field and measure the dipolar coupling strength to the cavity mode to be $78 pm 4 mathrm{mu eV}$, fully consistent with the 82 $mathrm{mu eV}$ predicted by theory. The emission from the cavity mode shows clear threshold-like behaviour. We observe a superlinear power dependence accompanied by a narrowing of the linewidth as the distinct features of lasing. The onset and prominence of these threshold-like behaviours are significant at resonance whilst weak off-resonance. Our results show that a lasing transition can be induced in interacting moir’e trapped IXs with macroscopic coherence extending over the lengthscale of the cavity mode. Such systems raise interesting perspectives for low-power switching and synaptic nanophotonic devices using 2D materials.

Published : "arXiv Mesoscale and Nanoscale Physics".