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5) The Nd : YAG laser transition at 1 .064 μ m has a Lorentzian shape with FWHM flu- of 195 GHz a...
Laser physics
4) A. Find the relation between spontaneous emission lifetime and cross-section for a simple atomic transition B. The laser transition of ruby has a Lorentzian shape of width (FWHM) 330 GHz at room temperature. Calculate the radiative lifetime when the transition cross-section is σ = 2.5x10-20 cm2 and the refractive index is n = 1.76