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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Polarization bistability and resultant spin rings in semiconductor microcavities
D Sarkar1, S S Gavrilov, M Sich
1Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom.
Physical Review Letters
|January 15, 2011
Summary
Pump laser polarization controls polariton interactions in semiconductor microcavities. This leads to spin rings and spatial patterns, explained by a semiclassical model including exciton reservoir effects.
Area of Science:
- Condensed matter physics
- Quantum optics
- Semiconductor physics
Background:
- Polaritons in semiconductor microcavities exhibit unique quantum phenomena.
- Spin-dependent interactions influence polariton behavior and light-matter coupling.
Purpose of the Study:
- To investigate the influence of pump laser polarization on polariton transmission.
- To explore the control of internal polarization and spatial patterns in microcavities.
- To model the observed phenomena using effective semiclassical equations.
Main Methods:
- Experimental transmission measurements of pump laser resonant with the lower polariton branch.
- Varying pump power and degree of circular polarization.
- Development and application of a phenomenological model with effective semiclassical equations of motion.
Main Results:
- Polariton transmission is highly sensitive to pump laser's circular polarization.
- Polariton-polariton interactions exhibit spin-dependent anisotropy, enabling polarization control.
- Polarization bistability leads to the formation of spatial patterns, specifically spin rings.
- A semiclassical model incorporating exciton reservoir interactions accurately describes experimental observations.
Conclusions:
- Pump polarization is a critical parameter for controlling polariton dynamics in microcavities.
- Spin-dependent interactions and exciton reservoir effects are essential for understanding observed phenomena.
- The study demonstrates a method for generating controlled spatial patterns through polarization engineering.
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