The Influence of Sub-Wavelength Effective Refractive Index Layer on the Transmittance of LYSO Scintillator

From various types of scintillating materials lutetium-yttrium oxyorthosilicate (LYSO) has the highest luminosity and the greatest potential of application in high-energy radiation detectors. Due to the small critical angle of total internal reflection the enhancement of the extraction of light outside a scintillator is a challenge. We study numerically the influence of the effective refractive index layer on the transmittance of LYSO crystal. It is possible to realize such layer by sub-wavelength patterning of crystal surface using for example focused ion beam. The enhancement of transmittance of LYSO crystal up to 100% as well as the possibility to tune the positions of transmittance maxima have been shown.