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Polarization eigenstates analysis of helically structured thin films.
Optics Express
|October 19, 2022
Summary
Researchers explored anisotropic thin films using Jones matrices to reveal polarization eigenstates and eigenvalues. They discovered exceptional points where eigenvectors coalesce, offering new insights beyond traditional optical properties.
Area of Science:
- Optics and Photonics
- Materials Science
- Condensed Matter Physics
Background:
- Optical properties of thin films are typically assessed using direct photometric measurements.
- Anisotropic thin films exhibit complex optical behaviors not fully captured by standard methods.
Purpose of the Study:
- To demonstrate that analyzing polarization eigenstates and eigenvalues of Jones matrices provides deeper insights into anisotropic thin films.
- To investigate the optical response of helically structured thin films, including circular Bragg resonance.
Main Methods:
- Numerical simulations and experimental measurements were employed.
- The study computed polarization eigenstates and eigenvalues of Jones matrices for thin films.
- Investigated wavevector space regions and identified exceptional points.
Main Results:
- Eigenvectors of the Jones matrices were found to be orthogonal in most wavevector regions.
- Deviations from orthogonality occur near circular Bragg and oblique resonances.
- Exceptional points were identified where eigenvectors coalesce, indicating a defective Jones matrix.
Conclusions:
- Analyzing polarization eigenstates and eigenvalues offers advanced understanding of anisotropic thin films.
- Exceptional points in wavevector space are critical features of these films.
- The observed properties of exceptional points are linked to reciprocity principles, including time reversal symmetry for lossless materials.
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