Ultrabroad Mid-Infrared Tunable Cr:ZnSe Channel Waveguide Laser

Operation of a Cr:ZnSe external-cavity waveguide laser is demonstrated with a CW tuning range of 700 nm from 2077-2777 nm (700 nm or 36 THz), the widest tuning range demonstrated by a waveguide laser. Narrow linewidths as low as 53 pm FWHM (3 GHz) are achieved and a maximum output power of 120 mW is attained at 2446 nm with over 15 mW available across the entire tunable range. A theoretical model is presented allowing the effect of changes to the system to be quantified in terms of laser performance; this allows the limitations of the architecture to be assessed. Good agreement is seen between the model and the experimental values obtained.