Highly Polarized Single-Photon Emission from Localized Excitons in a WSe₂/CrSBr Heterostructure

Area of Science:

• Quantum physics
• Materials science
• Condensed matter physics

Background:

• Single-photon emitters (SPEs) are essential for quantum technologies.
• Existing SPEs in 2D materials often rely on strain or out-of-plane magnetic ordering.
• Proximity effects in 2D heterostructures offer new avenues for quantum emitter design.

Purpose of the Study:

• To investigate a novel heterostructure for single-photon emission.
• To explore magnetic field effects on SPE properties.
• To develop magnetically tunable quantum emitters.

Main Methods:

• Fabrication of a WSe2 monolayer suspended on few-layer CrSBr.
• Optical spectroscopy to characterize SPEs.
• Application of in-plane and out-of-plane magnetic fields to study energy shifts and polarization.

Main Results:

• Identification of a bright SPE with high polarization selection in the WSe2/CrSBr heterostructure.
• Observation of an energy shift in the SPE, correlated with the CrSBr metamagnetic transition under an in-plane magnetic field.
• Demonstration of SPE sensitivity to both in-plane and out-of-plane magnetic fields, unlike conventional SPEs in WSe2.

Conclusions:

• The WSe2/CrSBr heterostructure hosts a novel, magnetically responsive single-photon emitter.
• This system exhibits a unique proximity-type effect influenced by the antiferromagnet's magnetic ordering.
• The tunable nature of this SPE at low magnetic fields presents a promising platform for advanced quantum technologies.