Atomic Percent

Atomic percent or at.% is a measure of concentration of dopant, used in chemistry, physics of solid state lasers and spectroscopy. The meaning of this term strongly depends on the context, host material and dopant. In particular, atomic percent may refer to: (A) Molar fraction [1] [2], which is ratio
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the number of atoms of an element per unit volume divided by the number of atoms per unit volume of the substance containing the element.