Patent ID: 8808656

Claim:
A garnet single crystal represented by a general formula, A 3 B 2 C 3 O 12 , wherein the garnet single crystal has a structure with three sites A, B and C occupied by cations, wherein A represents an element occupying the site A, wherein B represents an element occupying the site B, wherein C represents an element occupying the site C, and wherein O represents an oxygen atom; wherein the garnet single crystal is a single crystal selected from the group consisting of Y 3 Al 5 O 12 , Lu 3 Al 5 O 12 and (Y 1-x Lu x ) 3 Al 5 O 12 , wherein 0<x<1; and wherein the garnet single crystal contains fluorine as an element for attaining any one or both of substituting for the oxygen atom or compensating for oxygen defect.