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Characterising energy transfer upconversion in Nd-doped vanadates at elevated temperatures.
Optics Express
|April 4, 2018
Summary
This study measured Energy Transfer Upconversion (ETU) in Nd-doped YVO4 and GdVO4 crystals. Results show decreased absorption cross-section and ETU coefficients with increasing temperature.
Area of Science:
- Materials Science
- Solid-State Physics
- Laser Technology
Background:
- Neodymium-doped vanadates (Nd:YVO4, Nd:GdVO4) are crucial laser materials.
- Understanding temperature-dependent optical properties is vital for device performance.
Purpose of the Study:
- To investigate the temperature dependence of Energy Transfer Upconversion (ETU) in Nd:YVO4 and Nd:GdVO4.
- To characterize the ground state absorption cross-section at elevated temperatures.
Main Methods:
- Automated z-scan technique for macroparameter measurement.
- Temperature-controlled measurements from room temperature (RT) to 450K.
- Characterization of 808 nm π-polarisation absorption cross-section.
Main Results:
- Absorption cross-section decreased with temperature for both Nd:YVO4 and Nd:GdVO4.
- ETU coefficients also showed a decrease across the measured temperature range.
- Specific values for absorption cross-section and ETU were quantified for different doping concentrations.
Conclusions:
- Temperature significantly impacts ETU and absorption properties in Nd-doped vanadates.
- These findings are critical for designing high-power, temperature-stable solid-state lasers.
- The z-scan technique provides an efficient method for such characterization.
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