Modification of microstructural, mechanical and optical properties with carbon ion irradiation in Y2SiO5 crystals

• High fluences Carbon-ion irradiation led to the structural degradation and changes the stress field in the Y 2 SiO 5 crystal. • Optical band gap energy E g decreased from5.77 eV to 5.44 eV after ion irradiation. • Formed waveguide of “well + barrier” type and “barrier” type after irradiation with 6 MeV C ions at different fluence. • Ion beam tecyhniques can be used to modify materials. Yttrium orthosilicate Y 2 SiO 5 crystals, a member of the silicate family, are versatile and multifunctional materials when doped with rare earth or transition metal ions. However, there have been limited investigations into the impact of ion irradiation on the crystal structure of Y 2 SiO 5 crystals to date. In this paper, the effect of microstructure, mechanical and optical properties of Y 2 SiO 5 crystal before and after different fluences of carbon ions irradiation was investigated utilizing complementary characterization techniques. The results indicate that carbon ion irradiation caused lattice disorder and damage, which resulted in structural deterioration and changes in optical properties, such as decrease in the optical band gap energy (from5.77 eV to 5.44 eV), changes in the effective refractive index ( n eff ) which resulted in the formation of “well + barrier” type and “barrier” type waveguides. In addition, elastic modulus increased after carbon ion irradiation. The results will be helpful for understanding the damage study of the Y 2 SiO 5 crystal with carbon ion irradiation and proving that ion beam techniques can be used for material modification.