Abstract

The real and imaginary parts of the complex index of refraction have been measured in the R₁ line of optically pumped ruby. The experiments, which employed a temperature-controlled, single-mode ruby laser as a variable-frequency monochromatic source, were performed near liquid-nitrogen temperature, where the R₁ doublet structure is well resolved. R₁ absorption profiles were measured for several optical-pumping conditions, ranging from zero up to a pump power that excited a population in the ²E state equal to about 60% of the population of the ⁴A₂ ground state. For each pumping condition, the anomalous-dispersion curve was measured interferometrically. The spectral profiles of the absorption coefficient and the anomalous dispersion display a dependence on the optical-pumping conditions that is more complicated than simple saturation of the R₁ transitions, but for given pumping conditions the two quantities are correlated as predicted by the Kramers–Kronig relations.

© 1973 Optical Society of America

Nonlinear Absorption of Coherent Resonance Radiation in Pink Ruby

Robert C. Mitchell and Jerald R. Izatt
Appl. Opt. 7(1) 77-81 (1968)

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