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Waveguide structures with antisymmetric gain/loss profile
Jiří Ctyroký1, Vladimír Kuzmiak, Sergey Eyderman
1Institute of Photonics and Electronics AS CR, vvi, Chaberská 57, 18251 Prague 8, Czech Republic. ctyroky@ufe.cz
Optics Express
|October 14, 2010
Summary
Antisymmetric gain/loss waveguides exhibit unusual power transmission. A confined, unattenuated TM polarized surface wave propagates at the interface of balanced loss and gain media, consistent with analytical models.
Area of Science:
- Photonics
- Waveguide Optics
- Metamaterials
Background:
- Antisymmetric gain/loss waveguide structures were initially benchmarks for beam propagation methods.
- Recent research explores these structures as photonic analogues of parity-time (PT) symmetry breaking in quantum mechanics.
Purpose of the Study:
- To describe the properties of two-mode waveguides and directional couplers with balanced loss and gain.
- To demonstrate unusual power transmission phenomena in these optical systems.
Main Methods:
- Numerical simulations were employed to investigate waveguide properties.
- Analytical modeling was used to validate findings.
Main Results:
- Unusual power transmission characteristics were observed in waveguides with balanced gain and loss.
- A confined, unattenuated TM polarized surface wave was found to propagate at the interface between gain and loss media.
Conclusions:
- The interface between balanced gain and loss media supports a unique surface wave.
- The properties of this surface wave align with predictions from a simple analytical model.
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