The piezospectroscopic (PS) coefficients relating frequency shift to pressure are evaluated for Sm3+ in the Al2O3-Y2O3 system compounds, which include Al2O3, Y3Al5O12, YAlO3, Y4Al2O9, and Y2O3. The fluorescence peaks are inherently narrow for all the synthesized compounds, on the basis of the f-f transition nature of Sm3+ ion. Furthermore, the PS coefficients are ranged from -2.2 to -8.2 cm-1/GPa, which are similar to the reported value for the R1 line of ruby and suitable for the PS stress evaluation. PS stress distribution measurements are demonstrated with sintered Y3Al5O12 ceramics as a sample, with 50 mu m intervals, under a microscope.
Yasuo Iida, Shuji Sakaguchi, Takahisa Tsugoshi, and Masayoshi Ohashi, "Pressure Dependence of Laser-Induced Fluorescence of Sm3+ in Al2O3-Y2O3 System Compounds," Appl. Spectrosc. 53, 1623-1627 (1999)