Trace Gas Absorption Spectroscopy on a Chip

Tunable diode laser absorption spectroscopy (TDLAS) can be used for detecting trace amounts of gases by analyzing their MIR absorption spectra. The combination of TDLAS with photonic integrated circuit (PIC) chips could produce devices that are more compact, cheaper, and compatible with much smaller sample volumes than presently available. A present barrier to these devices is the lack of long, low-loss waveguides, with high interaction strength and negligible etalon effects. The development of such waveguides requires innovative designs, optimized MIR photonic materials and few and improved fabrication processes.