Energy transfer upconversion on neodymium doped phosphate glasses investigated by Z-scan technique

• We used the well known Z-scan technique to investigate an energy transfer process.
• Experimental setup and data analysis are simpler than in conventional techniques.
• Experimental data indicates that the ETU process is due to energy migration, mainly.
• It is possible to use such a data to calculate the parameters needed to design some optical devices.

Time-resolved Z-scan measurements were employed to characterize energy transfer upconversion on the phosphate glass matrix, named PAN (P2O5–Al2O3–Na2CO3), doped with increasing Nd3+ concentrations. It was observed a linear dependence of the upconversion parameter with the dopant agent, which indicates the presence of a static and dynamic energy transfer processes. The critical inversion density was also evaluated for the same set of samples.