Thermal Dependence of Ruby Laser Emission

Abstract
The temperature shift of ruby laser emission has been measured interferometrically for temperatures between 66° and 210°K. Representative values of the temperature shift coefficient are 0.004 Å/K° at 66°K, 0.014 Å/K° at 100°K, and 0.046 Å/K° at 200°K. These results are in excellent agreement with calculations by McCumber and Sturge which were based on Raman scattering of Debye‐model phonons. The experimental technique for measuring the wavelength shifts is described in detail, and the results are compared with earlier measurements of the temperature dependence of ruby R1 absorption and ruby laser emission.