The empty d-shell Ti4+ metal ion is contributing to large increases of the linear and non-linear indices of the glasses [23,38,39], where titanium–oxygen entities are considered as the main factor contributing to hyperpolarizability of the glass
The empty d-shell Ti4+ metal ion is contributingto large increases of the linear and non-linear indices of theglasses [23,38,39], where titanium–oxygen entities are consideredas the main factor contributing to hyperpolarizability of the glass