Progress towards Whispering Gallery Mode Resonator based Spectroscopy in Mid-Infrared

摘要

We present studies of using high Q whispering gallery mode resonators in Mid-IR laser spectroscopy. Several crystalline materials have high transparency in Mid-IR wavelength region and can be made into high Q optical resonators. We report recent measurements of Q values of greater than 1×10~8 in the wavelength region longer than 3 μm using one of these materials, Magnesium Fluoride (MgF_2). These resonators are being used for cavity ring-down measurements, optical frequency comb generation, and their applications in Mid-IR spectroscopy.