Polarization stabilized VCSELs by displacement Talbot lithography-defined surface gratings

Polarization-stable vertical-cavity surface-emitting lasers (VCSELs) with a simple fabrication process are presented. The gratings fixing the polarization are defined by a two-step exposure technology taking advantage of the displacement Talbot lithography technique. This enables grating lines to remain within the inner circle mesa of the VCSELs. These surface grating VCSELs with different periods are theoretically modeled and experimentally verified. Most of these VCSELs exhibit full polarization stability as predicted theoretically. For VCSELs with grating periods larger than the emission wavelength we found a weak orthogonal polarization suppression ratio, thereby deviating from those grating VCSELs with smaller periods.