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Dynamically crossing diabolic points while encircling exceptional curves: A programmable symmetric-asymmetric
Ievgen I Arkhipov1, Adam Miranowicz2,3, Fabrizio Minganti4,5
1Joint Laboratory of Optics of Palacký University and Institute of Physics of CAS, Faculty of Science, Palacký University, 17. listopadu 12, 771 46, Olomouc, Czech Republic. ievgen.arkhipov@upol.cz.
Nature Communications
|April 12, 2023
Summary
Researchers demonstrate a novel method for controlling light in non-Hermitian photonic systems. By winding around exceptional curves and crossing diabolic points, they achieve precise asymmetric-symmetric mode switching in multimode systems.
Area of Science:
- Quantum physics
- Photonics
- Non-Hermitian systems
Background:
- Non-Hermitian systems exhibit unique spectral properties not found in Hermitian systems.
- Exceptional points (EPs) in two-mode systems allow controlled asymmetric-symmetric mode switching.
- Multimode systems with higher-order EPs face challenges in controlling mode switching due to adiabaticity breakdown.
Purpose of the Study:
- To overcome limitations in controlling mode switching in multimode non-Hermitian systems.
- To demonstrate a new method for precise light manipulation in complex photonic setups.
- To explore the role of exceptional curves and diabolic points in multimode systems.
Main Methods:
- Investigating a four-mode [Formula: see text]-symmetric bosonic system.
- Dynamically winding around exceptional curves.
- Crossing diabolic points in conjunction with exceptional curves.
Main Results:
- Successfully demonstrated controlled asymmetric-symmetric mode switching in a four-mode system.
- Overcame adiabaticity breakdown issues present in higher-order EP scenarios.
- Showcased the efficacy of combining exceptional curve winding with diabolic point crossings.
Conclusions:
- The proposed method offers a robust way to control light in multimode non-Hermitian photonic systems.
- Crossing diabolic points alongside exceptional curves provides a viable solution for mode switching challenges.
- This work opens new avenues for advanced light manipulation in photonic devices.
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