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Updated: Jul 8, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Rashba-like spin splitting in inversion symmetric plasmonic metasurface
Sujit Rajak1, Nishkarsh Kumar2, Dheeraj Yadav1
1Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, W.B., India.
Summary
Researchers discovered a novel spin-split dispersion in plasmonic crystals, driven by a geometric linear birefringence-linear dichroism effect. This finding enables new spin-based dispersion engineering in symmetric nanostructures for advanced spin optics.
Area of Science:
- Condensed matter physics
- Plasmonics
- Nanophotonics
Background:
- Spin-orbit interaction (SOI) typically requires broken spatial inversion symmetry.
- Existing spin optics research often excludes symmetric metastructures.
Purpose of the Study:
- To report an extraordinary spin-split dispersion effect in an inversion-symmetric plasmonic crystal.
- To identify the mechanism behind this spin-split dispersion.
Main Methods:
- Momentum domain polarization analysis.
- Investigating leaky surface plasmons in plasmonic crystals.
- Analyzing geometric linear birefringence-linear dichroism (LB-LD).
Main Results:
- Observed spin-split dispersion in an inversion-symmetric plasmonic crystal.
- Identified a transverse momentum-dependent geometric LB-LD effect as the cause.
- Demonstrated that geometric phase gradient mediates spin-split dispersion via spin-dependent transverse momentum.
Conclusions:
- Unconventional SOI phenomena observed in symmetric metastructures.
- Presents a new paradigm for spin-based dispersion engineering.
- Enables spin-controlled nano-optical functionalities in previously excluded symmetric systems.
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