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Depolarization and principal mueller matrix measured by null ellipsometry.
Applied Optics
|March 28, 2008
Summary
New null ellipsometry methods accurately measure depolarization and Mueller matrices. These techniques correct for measurement errors, showing excellent agreement with sapphire slab depolarization spectra.
Area of Science:
- Optical physics
- Ellipsometry
- Spectroscopy
Background:
- Accurate measurement of optical properties like depolarization and Mueller matrices is crucial for material characterization.
- Null ellipsometry and rotating analyzer ellipsometry are established techniques, but error correction is essential for precision.
Purpose of the Study:
- To devise and validate methods for accurate depolarization and principal Mueller matrix measurement using null ellipsometry.
- To analyze and correct for measurement errors inherent in these techniques.
- To compare directly measured depolarization spectra with indirectly derived and simulated spectra.
Main Methods:
- Development of novel null ellipsometry techniques for measuring depolarization and principal Mueller matrices.
- Analysis of measurement errors associated with the devised methods.
- Implementation of error correction strategies.
- Direct measurement of depolarization spectrum for a sapphire slab.
- Indirect reduction of depolarization spectrum from retardance spectrum obtained via rotating analyzer ellipsometry.
- Simulation of depolarization spectrum considering monochromator bandwidth effects.
Main Results:
- The devised null ellipsometry methods provide accurate measurements of depolarization and Mueller matrices.
- Measurement errors were identified and effective correction methods were developed.
- Directly measured depolarization spectrum for a sapphire slab showed excellent agreement with indirectly reduced and simulated spectra.
- Cross-polarized depolarization for the sapphire slab was found to be significantly lower than total depolarization.
Conclusions:
- The developed null ellipsometry methods are effective for precise optical characterization.
- Error correction is vital for reliable depolarization and Mueller matrix measurements.
- The findings validate the accuracy of the new methods and provide insights into material depolarization characteristics.
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