arXiv subjects

Teemu Tomberg

Publications and source records attributed to Teemu Tomberg.

3 recordsLinked to original sources

arXiv2020

High-resolution analysis of the ${ν_3}$ band of radiocarbon methane $^{14}CH_{4}$

We present the first high-resolution measurements and rotational analysis of the fundamental asymmetric stretching vibrational band ${ν_3}(F_2)$ of radiocarbon methane. A spectrometer consisting of a mid-infrared continuous-wave optical parametric oscillator and a cantilever-enhanced photoacoustic detector was employed to determine the wavenumbers of 43 rovibrational lines. A spectroscopic model could reproduce all the observed transition wavenumbers within the accuracy of the experiment. Our work contributes to the development of radiocarbon methane detectors based on laser spectroscopy.

physics.chem-ph↗

arXiv2019

Broadband photoacoustic spectroscopy of $^{14}\text{CH}_4$ with a high-power mid-infrared optical frequency comb

We report a photoacoustic spectroscopy setup with a high-power mid-infrared frequency comb as the light source. The setup is used in broadband spectroscopy of radiocarbon methane. Due to the high sensitivity of a cantilever-enhanced photoacoustic cell and the high power light source, we can reach a detection limit below 100 ppb in a broadband measurement with a sample volume of only a few milliliters. The first infrared spectrum of $^{14}\text{CH}_4$ is reported and given a preliminary assignment. The results lay a foundation for the development of optical detection systems for radiocarbon methane.

physics.optics↗

arXiv2017

Sub-part-per-trillion level detection of hydrogen fluoride by cantilever-enhanced photo-acoustic spectroscopy

We present a highly sensitive hydrogen fluoride detector based on simple cantilever-enhanced photo-acoustic spectroscopy. A noise equivalent concentration of 5 parts-per-trillion was achieved in 1 s and 650 parts-per-quadrillion in 32 min. The limits were reached with an average optical power of 950 mW using a new continuous-wave optical parametric oscillator at 2.476 μm. The achieved normalized noise equivalent absorption coefficient was 2.7$\times$10$^{-10}$ Wcm$^{-1}$ Hz$^{-1/2}$.

physics.ins-det↗