Note: a high transmission Faraday optical isolator in the 9.2 μm range.

We have fabricated and characterized an n-doped InSb Faraday isolator in the mid-IR range (9.2 μm). A high isolation ratio (31(2) dB) and low insertion loss (1.

Frequency doubling of CO2 laser radiation at 10.6 microm in the highly nonlinear chalcopyrite LiGaTe2.

Type-I phase matching for second-harmonic generation at 10.6 microm in LiGaTe(2) is demonstrated by using a tunable single-frequency continuous-wave CO(2) laser, and the nonlinear coefficient of LiGaTe(2) is determined from comparison with AgGaSe(2). The effective nonlinearity of LiGaTe(2) for this process amounts to 34.

Narrow-line phase-locked quantum cascade laser in the 9.2 microm range.

We report the operation of a 50 mW continuous-wave quantum cascade laser (QCL) in the 9.2 microm range, phase locked to a single-mode CO(2) laser with a tunable frequency offset. The wide free-running emission spectrum of the QCL (3-5 MHz) is strongly narrowed down to the kilohertz range, making it suitable for high-resolution molecular spectroscopy.