A VCSEL waveguide grating coupler is provided such that a first and second
mirror are positioned to define a resonant cavity between them. The
waveguide grating coupler further includes a waveguide having a first
grating formed as a part of the waveguide to couple light of a first
polarization mode into the waveguide. A second grating is formed on the
waveguide grating coupler and is orthogonal to the first grating. The
second grating is operative to enhance the light coupled to the waveguide
by creating a loss difference between light of the first polarization
mode and light of a second polarization mode, so that light of the first
polarization mode lases preferentially within the VCSEL.