A novel, simple and low-cost external cavity laser using subwavelength resonant grating filter

A novel, stable external cavity laser with subwavelength resonant grating filter is demonstrated. The SRG-ECL consists of a single Fabry-Perot (FP) laser with a high reflectivity facet and a low reflectivity facet, plus a wavelength selective reflector (SRG filter) as one facet of the external cavity. The laser shows high side mode suppression ratio, high output power, high polarization extinction ratio, and low threshold current. It can be readily integrated with other optical elements, and is simple and potentially inexpensive to implement. With these advantages, it can be a viable light source for future applications in areas such as fiber-optic communications.