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Updated: Jul 18, 2025

Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Room temperature valley polarization via spin selective charge transfer.
Shreetu Shrestha1, Mingxing Li2, Suji Park2
1Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, 11973, USA. sshrestha@bnl.gov.
Researchers achieved room temperature valley polarization in transition metal dichalcogenides using chiral perovskites. This breakthrough in valleytronics utilizes spin-selective charge transfer for quantum information applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Quantum Information Science
Background:
- Transition metal dichalcogenides (TMDs) possess degenerate valleys crucial for quantum information processing.
- Maintaining valley polarization at room temperature is challenging due to phonon-induced scattering.
Purpose of the Study:
- To demonstrate room temperature valley polarization in TMD heterostructures.
- To explore the use of chiral perovskites as spin filters for valley polarization.
Main Methods:
- Fabrication of heterostructures using monolayer MoS2 and chiral lead halide perovskites.
- Optical excitation with linearly polarized light.
- Measurement of helicity-resolved photoluminescence.
Main Results:
- Achieved room temperature valley polarization up to -7% and 8% in MoS2/R-(+)- and MoS2/S-(-)- perovskite heterostructures.
- Demonstrated spin-selective charge transfer from MoS2 to chiral perovskites.
- Identified chiral perovskites as effective spin filters.
Conclusions:
- The study presents a robust method for achieving room temperature valley polarization.
- This approach paves the way for practical valleytronics devices.
- Chiral perovskites offer a promising route for spin filtering in quantum technologies.
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