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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Topological Spaser
Jhih-Sheng Wu1, Vadym Apalkov1, Mark I Stockman1
1Center for Nano-Optics (CeNO) and Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA.
Physical Review Letters
|January 25, 2020
Summary
Researchers developed a topological spaser using plasmonic nanoshells. This device exhibits bistability, enabling ultrafast optical memory and chiral sensing applications.
Area of Science:
- Plasmonics
- Topological photonics
- Condensed matter physics
Background:
- Spasers (Surface Plasmon Amplification by Stimulated Emission of Radiation) are nanoscale lasers.
- Topological concepts are increasingly applied to control light propagation.
- Chiral light-matter interactions are crucial for sensing and information processing.
Purpose of the Study:
- To theoretically introduce a novel topological spaser.
- To investigate its light generation properties and potential applications.
- To explore spontaneous symmetry breaking in plasmonic systems.
Main Methods:
- Theoretical modeling of a hexagonal array of plasmonic metal nanoshells.
- Analysis of surface plasmon modes in K and K' valleys.
- Investigation of mode competition and bistability.
Main Results:
- Generation of two mutually time-reversed chiral surface plasmon modes with opposite topological charges (±1).
- Observation of spontaneous symmetry breaking due to mode competition, leading to bistability.
- Identification of a two-dimensional E' representation of the D3h point symmetry group for the modes.
Conclusions:
- The proposed topological spaser demonstrates unique chiral light generation.
- Its bistability offers potential for ultrafast all-optical memory and information processing.
- The device shows promise for advanced biomedical detection and sensing with chirality resolution.
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