Robust optical emission polarization in MoS 2 monolayers through selective valley excitation

We report polarization resolved photoluminescence from monolayer ${\mathrm{MoS}}_{2}$, a two-dimensional, noncentrosymmetric crystal with direct energy gaps at two different valleys in momentum space. The inherent chiral optical selectivity allows exciting one of these valleys, and close to 90$%$ po... View More