High-performance wavelength tuning of a mid-infrared solid-state laser using a resonant diffraction grating

We report the first demonstration of laser wavelength tuning with a resonant grating in the mid-infrared spectral domain and with Littrow mounting of the grating. We show for a mid-infrared Cr:ZnSe solid-state laser that this tuning technique is much more wavelength selective than prism-based tuning, while inducing significantly lower cavity losses than in the case of a standard metal-coated grating. Furthermore, the resonant grating allows tuning the Cr:ZnSe laser over as much as 400 nm around a center wavelength of 2.38 mu m. This shows the potential of employing Littrow-mounted resonant diffraction gratings for controlling and tuning the emission wavelength of lasers emitting in the mid-infrared spectral domain and other wavelength regions.