Abstract

Electroreflectance vibrational spectroscopy^1-4 (EVS) is an infrared technique for obtaining extremely high resolution spectra of adsorbed species. Light from a tunable infrared diode laser is reflected from an adsorbate covered surface to a detector. The reflected light is modulated by using a large electric field to shift adsorbate vibrational frequency - the Stark effect. Sensitivity to fractional modulation as low as 2x10⁻⁸ Hz^−1/2, near the shot noise limit, is obtained. The high sensitivity and zero background nature of EVS also allow absolute measurements of the Stark tuning rate to be made.

© 1985 Optical Society of America