Advances in MOEMS-Based External Cavity QCLs

The combination of broadband quantum cascade lasers (QCLs) with a micro-electro-mechanical system (MOEMS) scanner with integrated diffraction grating as a wavelength-selective and optical feedback providing element enables the realization of compact, portable and robust spectroscopy systems. As previously showed [12], such MOEMS-based external cavity (EC)-QCLs configurations lead to measurement times as low as ∼1 millisecond per QCL-tuning range (hundreds of cm−1) while eliminating the need of homodyne detection systems, such as lock-in electronics. Also non-resonant (quasistatic) MOEMS grating scanners providing scan rates of tens of Hz as well as static setting of arbitrary wavelengths are possible, keeping the advantage of using small MOEMS footprints, ruggedness, and low power consumption.