Intracavity laser spectroscopy

Silylene SiH2 was directly detected during the pyrolytic decomposition of silane (and ethylsilane EtSiII3) for the first time by intracavity laser spectroscopy in 198865. The high detection sensitivity of this experiment allowed the pyrolysis mechanism to be examined under conditions that optimized film growth rather than spectroscopic conditions. 

Fig. 1.14 Experimental arrangement for intracavity laser spectroscopy using a step-function pump intensity and a definite delay for the detection [13]...

A. Campargue, F. Stoeckel, M. Chenevier, High sensitivity intracavity laser spectroscopy applications to the smdy of overtone transitions in the visible range. Spectrochim. Acta Rev. 13, 69 (1990)... 

A.A. Kaschanov, A. Charvat, F. Stoeckel, Intracavity laser spectroscopy with vibronic sohd state lasers. J. Opt. Soc. Am. B 11, 2412 (1994)... 

V.R. Mironenko, V.I. Yudson, Quantum statistics of multimode lasing and noise in intracavity laser spectroscopy. Sov. Phys. JETP 52, 594 (1980)... 

E.A. Sviridenko, M.P. Erolov, Possible investigations of absorption line profiles by intracavity laser spectroscopy. Sov. J. Quantum Electron. 7, 576 (1977)... 

K. Strong, T. J. Johnson, G.W. Harris, Visible intracavity laser spectroscopy with a step-scan Fourier-transform interferometer. Appl. Opt. 36, 8533 (1997)... 

Applications So far, intracavity laser spectroscopy has been applied primarily to the detection of absorption spectra of gaseous impurities such as NH3 and CH4 in the near-infrared region using a tunable broadband laser. Special DLs designed with an external cavity have also been investigated recently for this purpose. CRS has been applied successfully to trace element detection using the ICP as the atomization system. The detection limits observed are at sub-parts per billion level (e.g., 0.3 ng ml for lead) and comparable to the detection limits achieved with ICP-MS. 

RE. Toschek, V.M. Baev One is not enough Intracavity laser spectroscopy with a multimode laser . In Laser Spectroscopy and New Ideas, ed. by... 

Plasma dissociation of gaseous B2H6 leads to the formation of BH2, which may be observed by intracavity laser spectroscopy. The observations, however, do not establish whether the BH2 is formed directly from B2H6 or results solely from secondary chemistry [6]. Pyrolysis studies have not answered this question, although a recent computational study has probed the early stages of B2H6 pyrolysis using many-body perturbation theory (MBPT) and the coupled-cluster approximation. The study considers two elementary processes which are viewed as key steps in the pyrolysis of diborane [7] ... 

It will be noted, however, that the losses due to reflection of light from mirrors result in a shorter optical path. The method of intracavity-laser spectroscopy possesses no such disadvantage because the species studied is placed inside the cavity of a broad-band laser (for instance, in one using organic dyes). The great length of the optical path increases the method sensitivity as high as 10 particles/ cm [360, 411]. 

V.M. Baev, T.P. Belikova, E.A. Sviridenkov, A.F. Suchkov Intracavity laser spectroscopy with continuous and quasi-continuous lasers. Sov. Phys. - JETP 47, 21 (1978)... 

Scheme of the kinetic intracavity laser spectroscopy technique 1, active medium of the laser 2, reactor 3, mirrors 4, pulse lamps for photolysis of a mixture and pumping of the laser 5, feeding source for photolysis 6, feeding source for the laser 7, controlling unit 8, unit for time delay between photolyzing and laser pulses and P, detector of the spectrum. 

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