Repetitively Mode-Locked Cavity-Enhanced Absorption Spectroscopy (RML-CEAS) for Near-Infrared Gas Sensing
نویسندگان
چکیده
A Pound-Drever-Hall (PDH)-based mode-locked cavity-enhanced sensor system was developed using a distributed feedback diode laser centered at 1.53 µm as the laser source. Laser temperature scanning, bias control of the piezoelectric ceramic transducer (PZT) and proportional-integral-derivative (PID) feedback control of diode laser current were used to repetitively lock the laser modes to the cavity modes. A gas absorption spectrum was obtained by using a series of absorption data from the discrete mode-locked points. The 15 cm-long Fabry-Perot cavity was sealed using an enclosure with an inlet and outlet for gas pumping and a PZT for cavity length tuning. The performance of the sensor system was evaluated by conducting water vapor measurements. A linear relationship was observed between the measured absorption signal amplitude and the H₂O concentration. A minimum detectable absorption coefficient of 1.5 × 10-8 cm-1 was achieved with an averaging time of 700 s. This technique can also be used for the detection of other trace gas species by targeting the corresponding gas absorption line.
منابع مشابه
Cavity enhanced spectroscopy of high-temperature H(2)o in the near-infrared using a supercontinuum light source.
In this paper we demonstrate how broadband cavity enhanced absorption spectroscopy (CEAS) with supercontinuum (SC) radiation in the near-infrared spectral range can be used as a sensitive, multiplexed, and simple tool to probe gas-phase species in high-temperature environments. Near-infrared SC radiation is generated by pumping a standard single-mode fiber with a picosecond fiber laser. Standar...
متن کاملOn-chip spectroscopy with thermally tuned high-Q photonic crystal cavities
Articles you may be interested in High sensitivity and high Q-factor nanoslotted parallel quadrabeam photonic crystal cavity for real-time and label-free sensing Appl. Photonic crystal slot waveguide absorption spectrometer for on-chip near-infrared spectroscopy of xylene in water Appl. Measurements of total peroxy and alkyl nitrate abundances in laboratory-generated gas samples by thermal diss...
متن کاملTechnical Note: Using a high finesse optical resonator to provide a long light path for differential optical absorption spectroscopy: CE-DOAS
Cavity enhanced methods in absorption spectroscopy have seen a considerable increase in popularity during the past decade. Especially Cavity Enhanced Absorption Spectroscopy (CEAS) established itself in atmospheric trace gas detection by providing tens of kilometers of effective light path length using a cavity as short as 1 m. In this paper we report on the construction and testing of a compac...
متن کاملFast response cavity enhanced ozone monitor
Ozone is an important atmospheric gas due to its role in air quality and radiative forcing. A new method for sensitive, rapid monitoring of ambient ozone has been developed using a compact platform and relatively inexpensive components. Based on incoherent broadband cavity enhanced absorption spectroscopy (IBB-CEAS), the device utilizes an optical cavity of just 14.5 cm and 99.3 % reflective mi...
متن کامل