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Updated: Jun 30, 2025
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Inducing Circularly Polarized Single-Photon Emission via Chiral-Induced Spin Selectivity
Suryakant Mishra1, Eric G Bowes1, Somak Majumder1
1Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.
ACS Nano
|March 14, 2024
Summary
Researchers explored chiral-induced spin-selectivity (CISS) in polyaniline films to control electron spin transport. This work demonstrates CISS enables circularly polarized light emission from quantum dots, advancing spintronics and photonic device applications.
Area of Science:
- Spintronics and molecular electronics
- Quantum optics and photonics
- Materials science and nanotechnology
Background:
- The chiral-induced spin-selectivity (CISS) effect offers a mechanism for spin-polarized electron transport through helical nanostructures.
- Potential applications include the transduction of electronic spin information to circularly polarized light in nonreciprocal photonic devices.
Purpose of the Study:
- To quantify the CISS effect in helical polyaniline films.
- To demonstrate the induction of circularly polarized light emission from quantum dots using CISS.
- To elucidate the spin-dependent transport pathways responsible for the observed phenomena.
Main Methods:
- Magnetoconductive atomic force microscopy (mcAFM) to measure spin-selective electronic transport.
- Integration of CdSe/CdS core/shell quantum dots with polyaniline films.
- Time-resolved photoluminescence microscopy and Kelvin probe force microscopy.
Main Results:
- Quantification of chiral-induced spin-selective transport in helical polyaniline.
- Demonstration of circularly polarized photoluminescence from quantum dots with up to ~21% circular polarization.
- Measurement of radiative lifetime differences for left- and right-handed circularly polarized light emission.
- Establishment of an energy level diagram for spin-dependent transport pathways.
Conclusions:
- Helical polyaniline films exhibit significant CISS, enabling spin-polarized electron transport.
- The CISS effect facilitates the generation of circularly polarized light from quantum dots, showcasing a spin-photon transduction pathway.
- Understanding these spin-dependent pathways is crucial for developing advanced spintronic and photonic devices.
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