Noise-immune cavity-enhanced optical heterodyne molecular spectroscopy: Current status and future potential

Foltynowicz, Aleksandra; Schmidt, Florian M.; Ma, Weiguang; Axner, Ove

doi:10.1007/s00340-008-3126-z

Cited by 135 publications

(78 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Pioneering advances in laser light sources, measurement techniques, and detection systems have opened new windows of opportunity for many of those applications mentioned above. Measurement noise has been reduced and absorption sensitivity increased via modulation techniques [16,17], the use of high-finesse cavities [18], and the combination of the two in the NICE-OHMS method [19,20]. These efforts make possible impressive shot-noise-limited absorption sensitivities [19], very high signal-to-noise ratios [21], and the capability to measure ultra-weak molecular transitions [22].…”

Section: Introductionmentioning

confidence: 99%

Cavity-enhanced optical frequency comb spectroscopy in the mid-infrared application to trace detection of hydrogen peroxide

et al. 2012

Self Cite

View full text Add to dashboard Cite

Cavity-enhanced optical frequency comb spectroscopy in the mid-infrared application to trace detection of hydrogen peroxide. Abstract We demonstrate the first cavity-enhanced optical frequency comb spectroscopy in the mid-infrared wavelength region and report the sensitive real-time trace detection of hydrogen peroxide in the presence of a large amount of water. The experimental apparatus is based on a midinfrared optical parametric oscillator synchronously pumped by a high-power Yb:fiber laser, a high-finesse broadband cavity, and a fast-scanning Fourier transform spectrometer with autobalancing detection. The comb spectrum with a bandwidth of 200 nm centered around 3.76 µm is simultaneously coupled to the cavity and both degrees of freedom of the comb, i.e. the repetition rate and carrier envelope offset frequency, are locked to the cavity to ensure stable transmission. The autobalancing detection scheme reduces the intensity noise by a factor of 300, and a sensitivity of 5.4 × 10 −9 cm −1 Hz −1/2 with a resolution of 800 MHz is achieved (corresponding to 6.9 × 10 −11 cm −1 Hz −1/2 per spectral element for 6000 resolved elements). This yields a noise equivalent detection limit for hydrogen peroxide of 8 parts-per-billion (ppb); in the presence of 2.8 % of water the detection limit is 130 ppb. Spectra of acetylene, methane, and nitrous oxide at atmospheric pressure are also presented, A. Foltynowicz ( ) · Applied physics. B, Lasers and optics (Print),

show abstract

Section: Introductionmentioning

confidence: 99%

Cavity-enhanced optical frequency comb spectroscopy in the mid-infrared application to trace detection of hydrogen peroxide

et al. 2012

Self Cite

View full text Add to dashboard Cite

show abstract

“…Changing the demodulation phase allows either the absorption or dispersion FMS signal to be acquired. MATLAB is used to fit the measured NICE-OHMS lineshape function [15].…”

Section: Methodsmentioning

confidence: 99%

External cavity diode laser-based detection of trace gases with NICE-OHMS using current modulation

et al. 2015

Self Cite

View full text Add to dashboard Cite

Abstract:We combine an external cavity diode laser with noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) using current modulation. With a finesse of 1600, we demonstrate noise equivalent absorption sensitivities of 4.1 x 10 −10 cm −1 Hz -1/2, resulting in sub-ppbv detection limits for Doppler-broadened transitions of CH 4 at 6132.3 cm −1 , C 2 H 2 at 6578.5 cm −1 and HCN at 6541.7 cm −1 . The system is used for hydrogen cyanide detection from sweet almonds. "Design considerations in high-sensitivity off-axis integrated cavity output spectroscopy," Appl. Phys. B 92, 467-474 (2008).

show abstract

“…34 In this work, the velocity of the ions is modulated by a square wave voltage at 4 kHz applied to the drift tube and aperture plates. After the heterodyne RF signal is demodulated with the mixers, the velocity modulation signal is demodulated using the lock-in amplifiers.…”

Section: Modulation Scheme and Doppler Splittingsmentioning

confidence: 99%

Ultra-sensitive high-precision spectroscopy of a fast molecular ion beam

Mills

Siller

Porambo

et al. 2011

The Journal of Chemical Physics

View full text Add to dashboard Cite

Direct spectroscopy of a fast molecular ion beam offers many advantages over competing techniques, including the generality of the approach to any molecular ion, the complete elimination of spectral confusion due to neutral molecules, and the mass identification of individual spectral lines. The major challenge is the intrinsic weakness of absorption or dispersion signals resulting from the relatively low number density of ions in the beam. Direct spectroscopy of an ion beam was pioneered by Saykally and co-workers in the late 1980s, but has not been attempted since that time. Here, we present the design and construction of an ion beam spectrometer with several improvements over the Saykally design. The ion beam and its characterization have been improved by adopting recent advances in electrostatic optics, along with a time-of-flight mass spectrometer that can be used simultaneously with optical spectroscopy. As a proof of concept, a noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) setup with a noise equivalent absorption of ∼2 × 10 −11 cm −1 Hz −1/2 has been used to observe several transitions of the Meinel 1-0 band of N + 2 with linewidths of ∼120 MHz. An optical frequency comb has been used for absolute frequency calibration of transition frequencies to within ∼8 MHz. This work represents the first direct spectroscopy of an electronic transition in an ion beam, and also represents a major step toward the development of routine infrared spectroscopy of rotationally cooled molecular ions.

show abstract

Noise-immune cavity-enhanced optical heterodyne molecular spectroscopy: Current status and future potential

Cited by 135 publications

References 52 publications

Cavity-enhanced optical frequency comb spectroscopy in the mid-infrared application to trace detection of hydrogen peroxide

Cavity-enhanced optical frequency comb spectroscopy in the mid-infrared application to trace detection of hydrogen peroxide

External cavity diode laser-based detection of trace gases with NICE-OHMS using current modulation

Ultra-sensitive high-precision spectroscopy of a fast molecular ion beam

Contact Info

Product

Resources

About