An external laser cavity was constructed that utilizes polarization multiplexing to combine the emission from two gallium nitride blue laser diodes. A polarization-dependent narrow-band resonant mirror was designed to be the output coupler of this cavity, which locked both laser diodes at a fixed wavelength of 445.5 nm with a line-width of <0.5 nm. Output powers from this system approached 0.7 W while maintaining complete spectral control.
We have intermixed GaAs/(AlGa)As multiquantum structures for waveguides and lasers by 3 MeV Ar implantation and 850 °C, 30 min closed-tube annealing. Buried-heterostructure lasers defined by Ar mixing had threshold currents of 100 mA for 370-μm-long devices. As waveguides for 1.15 μm light, the devices exhibited losses of 25 cm−1 in the annealed, implanted regions, and 15 cm−1 in unimplanted regions defined by adjacent implants. Analysis of the results illustrates important considerations for implant mixing for waveguide formation.
This study reports design, fabrication, and characterization of high-performance guided-mode resonance (GMR) infrared filters based on germanium (Ge) operating in the 7 to 15 µm spectral region. The GMR filters exhibit deep transmittance nulls and high sideband efficiency functioning as band-stop filters. There is reasonable agreement between experimental and theoretical spectral results. By modifying design parameters and incorporating an anti-reflection (AR) layer on the substrate backside, the functionality of the filter is significantly enhanced. The measured low transmittance value of the fabricated filters is found to be as low as 0.021% corresponding to an optical density of OD = 3.68. The one-dimensional (1D) GMR filters produced exhibit agile wavelength tunability when the angle of incidence is varied. The results highlight the potential of GMR technology operating at long infrared wavelengths with creating high performance filters with tunable spectral characteristics. Anticipated application domains include the fields of sensing, imaging, and spectroscopy.
This study reports design, fabrication, and characterization of high-performance guided-mode resonance (GMR) infrared filters based on germanium (Ge) operating in the 7 to 15 µm spectral region. The GMR filters exhibit deep transmittance nulls and high sideband efficiency functioning as band-stop filters. There is reasonable agreement between experimental and theoretical spectral results. By modifying design parameters and incorporating an anti-reflection (AR) layer on the substrate backside, the functionality of the filter is significantly enhanced. The measured low transmittance value of the fabricated filters is found to be as low as 0.021% corresponding to an optical density of OD = 3.68. The one-dimensional (1D) GMR filters produced exhibit agile wavelength tunability when the angle of incidence is varied. The results highlight the potential of GMR technology operating at long infrared wavelengths with creating high performance filters with tunable spectral characteristics. Anticipated application domains include the fields of sensing, imaging, and spectroscopy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.