Related Experiment Video
Updated: Jan 17, 2026
12:57
Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
9.6K
Interplay between Chiro-Optical and Spin Transport Properties in Chiral CdSe Quantum Dots
Elizabeth Shiby1, Rui Sun2, Brian P Bloom1
1Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
ACS Nano
|September 22, 2025
Summary
The chiral-induced spin selectivity (CISS) effect
Area of Science:
- Condensed matter physics
- Quantum chemistry
- Materials science
Background:
- The chiral-induced spin selectivity (CISS) effect is a phenomenon where chiral molecules can induce spin polarization in charge carriers.
- Understanding the underlying physical mechanisms of CISS is crucial for its application in spintronics and quantum technologies.
- Current theories debate the exact nature of spin-dependent processes governed by CISS.
Purpose of the Study:
- To investigate structure-property relationships in chiral quantum dot assemblies.
- To identify key attributes of CISS-based phenomena by studying chiral cadmium selenide (CdSe) quantum dots.
- To correlate circular dichroism (CD) strength with spin current properties.
Main Methods:
- Fabrication and characterization of chiral CdSe quantum dot assemblies.
- Measurement of circular dichroism (CD) spectra to quantify chirality.
- Transport measurements to probe pure spin currents and spin-polarized charge currents.
Main Results:
- A direct correlation was observed between the CD strength of the primary exciton transition and CISS properties.
- Spin-polarized charge current directionality was found to be dependent on the CD signal's polarity.
- Pure spin current transport exhibited robustness against changes in CD signal polarity.
Conclusions:
- Chirality-induced splitting of spin sub-bands is a key factor modulating CISS phenomena.
- Symmetry breaking during charge transport through quantum dots influences spin-polarized currents.
- The study provides insights into the distinct behaviors of pure spin currents versus spin-polarized charge currents under CISS.
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