Comparative study on the linear thermal expansion coefficient of laser host crystals by first principles calculations

Abstract

We evaluated the linear thermal expansion coefficient (α) of various laser host crystals with cubic symmetry by first principles calculations, where the relation of calculated α was CaF2 >> Sc2O3 > ZnS > ZnSe ∼ Lu3Al5O12 > Y3Al5O12 > Y2O3 > Lu2O3 at 300 K. The variation of temperature dependent α for these materials in past reports are approximately 15%, and it is comparable to the difference from our calculated α. We also proposed numerical models for thermal expansion from 150 K to 900 K that reproduced our calculated α with the error below 2%.