Thermal phonon resonance in nitrogen gas observed by Brillouin scattering

Minami, Yasuo; Yogi, Takeshi; Sakai, Keiji

doi:10.1103/physreva.78.033822

Cited by 7 publications

(4 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…22,23 Gas-tight cells were filled with the specimen gas via a pressure regulator. The scattered light collinear with the reference light was detected by a highspeed avalanche-type photodiode ͑S5343 or S9073, Hamamatsu Photonics͒ and generated the optical beating signal.…”

Section: Methodsmentioning

confidence: 99%

Rotational relaxation in H2 gas observed with optical beating Brillouin spectroscopy

Minami

Yogi

Sakai

2009

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Methodsmentioning

confidence: 99%

Rotational relaxation in H2 gas observed with optical beating Brillouin spectroscopy

Minami

Yogi

Sakai

2009

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…. Following the approach used to obtain equation ( 11), we substitute ( 13) into (7) and set all ωτ = 1 i in µ…”

Section: Acoustic Spectra Of Multimode Relaxation Processesmentioning

confidence: 99%

“…In the past several decades, the study of molecular relaxation in gases has substantially promoted the development of many fields, such as anomalous absorption in polyatomic gases [1][2][3][4], molecular lasers [5,6], thermal phonons [7], quantum computation [8][9][10], plasma discharges [11,12] and so on. The frequency dependencies of acoustic absorption and sound speed both are determined by molecular relaxation in excitable gases [2,3].…”

Section: Introductionmentioning

confidence: 99%

Capturing molecular multimode relaxation processes in excitable gases based on decomposition of acoustic relaxation spectra

Zhu

Liu

Wang

et al. 2017

Meas. Sci. Technol.

View full text Add to dashboard Cite

Existing two-frequency reconstructive methods can only capture primary (single) molecular relaxation processes in excitable gases. In this paper, we present a reconstructive method based on the novel decomposition of frequency-dependent acoustic relaxation spectra to capture the entire molecular multimode relaxation process. This decomposition of acoustic relaxation spectra is developed from the frequency-dependent effective specific heat, indicating that a multi-relaxation process is the sum of the interior single-relaxation processes. Based on this decomposition, we can reconstruct the entire multi-relaxation process by capturing the relaxation times and relaxation strengths of N interior single-relaxation processes, using the measurements of acoustic absorption and sound speed at 2N frequencies. Experimental data for the gas mixtures CO2–N2 and CO2–O2 validate our decomposition and reconstruction approach.

show abstract

“…Gas composition detection based on the measurement of acoustic relaxation absorption and sound speed has been applied to the monitoring of gases [1][2][3][4], combustion systems [5,6], quantum computation [7,8], etc. Compared with other methods including thermal phonon resonance [9] and laser sensing [10,11], the acoustic relaxation method has several advantages such as low cost, fast response, and no necessity for calibration [12,13]. However, in practical gas applications, the measurement process of acoustic relaxation absorption is complex, and the measurement value is low accuracy [14].…”

Section: Introductionmentioning

confidence: 99%

Extracting relaxational features from measurements of sound speeds for gas sensing

Zhang,

Pan

et al. 2023

J. Inst.

View full text Add to dashboard Cite

In recent years, gas sensing methods by jointly measuring acoustic relaxation absorption and sound speeds have become a research focus in acoustic fields. However, the existing methods are difficult to be employed in practical gas detection due to complex measurement processes and large measurement errors when measuring the sound relaxational absorption. Furthermore, the acoustic relaxation absorption spectrum's small signal is hard to be measured because of the noise and large classical relaxation in the high-frequency range. In this paper, a gas sensing method is proposed by only measuring the sound speeds at the three frequencies, avoiding the problems of measuring the acoustic absorption spectrum. First, sound speeds are measured at three frequency points; second, the relaxation strength and the relaxation time of the acoustic relaxation features are extracted; finally, the absorption spectral peak is acquired and located for gas detection. The simulation results verify the feasibility of our method, and the detection errors from the measurement errors of sound speeds can be eliminated effectively. Thus, our work provides a high-accurate and simple acoustic method for gas sensing.

show abstract

Thermal phonon resonance in nitrogen gas observed by Brillouin scattering

Cited by 7 publications

References 23 publications

Rotational relaxation in H2 gas observed with optical beating Brillouin spectroscopy

Rotational relaxation in H2 gas observed with optical beating Brillouin spectroscopy

Capturing molecular multimode relaxation processes in excitable gases based on decomposition of acoustic relaxation spectra

Extracting relaxational features from measurements of sound speeds for gas sensing

Contact Info

Product

Resources

About