1.55 µm wavelength band photonic crystal surface emitting laser with n-side photonic crystal and operation at up to 85 °C.

We describe the structure, fabrication, and measured performance of a 1543 nm wavelength photonic crystal surface emitting laser. An asymmetric double lattice design was used to achieve single mode lasing with side mode suppression ratios >40 dB. The photonic crystal was formed using encapsulated air holes in an n-doped InGaAsP layer with an InGaAlAs active layer then grown above it. In this way a laser with a low series resistance of 0.32 Ω capable of pulsed output powers of 171 mW at 25 °C and 40 mW at 85 °C was demonstrated.

A novel single frequency stabilized Fabry-Perot laser diode at 1590 nm for gas sensing.

A novel single frequency stabilized Fabry-Perot (SFP) laser diode with an emission wavelength of lambda = 1590 nm for H2S gas sensing is reported. Sculpting of the multi-mode spectral distribution of a FP laser to achieve single frequency emission is carried out using post growth photolitographic processing of the device. The resulting longitudinal-mode controlled FP laser has a stabilized single frequency emission with a side mode suppression ratio (SMSR) of 40 dB. The application of this device to spectroscopic based H2S sensing is demonstrated by targeting absorption lines in the wavelength range 1588 < or = lambda < or = 1591 nm. Using wavelength modulation spectroscopy (WMS), a low detection limit of 120 ppm x m x Hz(-1/2) was estimated while targeting the absorption line at 1590.08 nm. These initial results demonstrate the potential of the stabilized FP laser diode at this wavelength as a tunable, single frequency source for spectroscopic based gas sensing.