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Electrically Tunable Momentum Space Polarization Singularities in Liquid Crystal Microcavities
Przemysław Oliwa1, Piotr Kapuściński1, Maria Popławska1
1Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, Warsaw, PL-02-093, Poland.
Summary
Researchers demonstrate electrical tuning of momentum space polarization singularities in liquid crystal microcavities. This breakthrough enables novel applications in spinoptronics and topological photonics.
Area of Science:
- Photonics
- Topological Photonics
- Liquid Crystal Optics
Background:
- Momentum space polarization singularities are vectorial twists in light's far-field patterns.
- They are linked to topological phenomena like bound states in the continuum and Berry curvature.
- Previous methods required complex photonic crystal designs with limited tunability.
Purpose of the Study:
- To demonstrate the generation and electrical tuning of momentum space polarization singularities.
- To explore their creation in a highly birefringent planar liquid crystal microcavity.
- To assess the potential for integration into spinoptronic technologies.
Main Methods:
- Utilized a highly birefringent planar liquid crystal microcavity with retained symmetries.
- Investigated the band structure for the emergence of polarization singularities.
- Applied electrical tuning to manipulate the singularities' properties.
Main Results:
- Successfully generated momentum space polarization singularities within the liquid crystal microcavity.
- Demonstrated precise electrical tunability of these singularities.
- Observed agreement between experimental results and theoretical predictions.
Conclusions:
- Momentum space polarization singularities can be generated and electrically tuned in liquid crystal microcavities.
- This offers a tunable platform for exploring topological photonic phenomena.
- Paves the way for integrating these singularities into advanced spinoptronic devices.
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