SENSITIVITY ENHANCEMENT OF LASER-ABSORPTION SPECTROSCOPY BY MAGNETIC ROTATION EFFECT

The use of magnetic rotation spectroscopy (Faraday effect) to reduce the effects of source noise and improve sensitivity of spectroscopy with color center lasers has been analyzed theoretically and tested experimentally on the vibrational overtone band of NO. Sensitivity improvement of a factor of 30 compared with simple Zeeman modulation has been demonstrated. As an example of this technique, the first observation of the fundamental vibrational band of the OH radical in absorption is reported. © 1980 American Institute of Physics.