  We propose a novel method for controlling the high-harmonic generation (HHG)
with a high dynamic range in single-layer graphene. We find that, by utilizing
shear strain, a significant enhancement or quenching of HHG is possible over a
range of several orders of magnitude. This feature is made possible by the
resonance mechanism at a van Hove singularity. Therein, the shear strain
controls the configurations of the two Dirac cones, resulting in changes in the
energy and dipole moment at the saddle point of the band dispersion. Our
findings provide a way for modulating or switching light by using a
nano-optomechanical device composed of single-layer graphene.
