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Updated: Jan 11, 2026
10:35
Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
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Topological chiral-gain in a Berry dipole material
Filipa R Prudêncio1,2, Mário G Silveirinha1
1University of Lisbon - Instituto Superior Técnico and Instituto de Telecomunicações, Avenida Rovisco Pais 1, 1049-001 Lisbon, Portugal.
Nanophotonics (Berlin, Germany)
|November 17, 2025
Summary
This study reveals how electric bias creates topological bandgaps in low-symmetry conductors, enabling unidirectional edge states. It also shows how chiral gain can generate lasing modes with orbital angular momentum.
Area of Science:
- Topological photonics
- Non-Hermitian optics
- Condensed matter physics
Background:
- Low-symmetry conductors with static electric bias can exhibit chiral gain.
- Chiral gain links a material's non-Hermitian optical response to the wave's spin angular momentum.
Purpose of the Study:
- To uncover the topological nature of chiral gain.
- To demonstrate how electric bias induces topological bandgaps and unidirectional edge states.
- To explore the generation of lasing modes with orbital angular momentum.
Main Methods:
- Theoretical investigation of topological band structures.
- Analysis of non-Hermitian optical response under electric bias.
- Modeling of boundary-confined lasing modes.
Main Results:
- Static electric bias induces topological bandgaps supporting unidirectional edge states.
- These edge states are typically dissipative.
- Operating outside the topological gap allows chiral gain to engineer boundary-confined lasing modes with electric-field-locked orbital angular momentum.
Conclusions:
- Chiral gain in low-symmetry conductors possesses topological characteristics.
- Electric bias can create topological bandgaps and control edge states.
- This work enables loss-compensated photonic waveguides and the generation of structured light with intrinsic orbital angular momentum.
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