Intracavity Laser Raman Spectroscopy Using a Commercial Laser

Abstract

The modification of a commercial laser for intracavity molecular scattering experiments is discussed. An improvement of almost 100 times in laser intensity is reported. Steps taken to eliminate an undesired secondary laser line produced by the laser because of the increase of laser intensity are presented.

Raman spectroscopy

“…The stray light rejection ability of a Cary 81 has been improved by two orders of magnitude (33), and a computer program to drive a sine-bar drive spectrometer in such a way as to give a constant scan in wavenumbers per unit time has been developed (34). Improvements to laser systems, both to reduce fluorescence from a dye laser (35) and to remove an unwanted laser line in a gas laser (36) have been described.…”

Rotational Temperature and Number Density Measurements of N2, O2, CO, and CO2 in a Hypersonic Flow Field Using Laser-Raman Spectroscopy

“…Since the high temperature ratio of ortho-to para-molecular species is assumed to be retained during the expansion process, one must regard the gas as a mixture of two inconvertible species. The partition functions for the ortho-specie q~M(o) and the para-specie q~M(p) are given by (17) and (18) where E' designates summing over (even J; odd J) integers if (_I)ap is (+ 1; -1) and a is the nucleon number of the atomic constituent and P, the electronic parity eigenvalue, is ±1. Then, E" denotes summing over the remaining integer set.…”

Cavity-Enhanced Raman Spectroscopy for Food Chain Management

“…A possible setup was described by J. J. Barrett et al in 1968, who moved a mirror of an ion laser and put the Raman sample into the laser cavity [ 65 ]. This was soon followed by G. O. Neely et al in 1972 and R. S. Hickman and L. Liang in 1973 [ 66 , 67 ], who named the technology Intracavity Raman spectroscopy. In 2003 Ohara et al introduced a similar mechanism with a laser diode [ 68 ], coupling an antireflection coated diode laser to a Fabry–Pérot cavity.…”