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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
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Temperature-Dependent Polarization Effects in Ce:LiLuF.
Applied Optics
|March 25, 2008
Summary
Crystal temperature significantly impacts Ce:LiLuF polarized emission. Cooling the crystal reduces excited-state absorption (ESA) and color center formation, enhancing laser performance and fluorescence yield.
Area of Science:
- Solid-state laser physics
- Materials science
- Optical spectroscopy
Background:
- Cerium-doped lithium lutetium fluoride (Ce:LiLuF) is a promising material for tunable lasers.
- Polarized emission characteristics are crucial for optimizing laser performance.
- Crystal temperature can influence optical properties and laser dynamics.
Purpose of the Study:
- To investigate the effect of crystal temperature on the polarized emission of Ce:LiLuF.
- To understand the underlying mechanisms affecting laser performance and fluorescence yield.
Main Methods:
- Tuned-laser studies
- Pump-probe-gain measurements
- Fluorescence yield spectroscopy
- Variable temperature experiments
Main Results:
- Sigma-polarized emission at 327 nm showed shorter buildup times, higher small-signal gains, but lower output power compared to pi-polarized emission.
- Excited-state absorption (ESA) and color center formation were more pronounced for sigma-polarized emission.
- Crystal cooling led to enhanced laser performance and fluorescence.
Conclusions:
- ESA is more severe for sigma-polarized emission in Ce:LiLuF, leading to reduced output power.
- Crystal cooling narrows the ESA absorption band, decreasing ESA probability and color center formation.
- Optimizing crystal temperature is critical for maximizing Ce:LiLuF laser efficiency and stability.
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