Acoustic Manipulation of Deterministic Quantum Emitters in WSe₂

Area of Science:

• Quantum physics
• Materials science
• Nanotechnology

Background:

• Surface acoustic waves (SAWs) are used to control excitonic states in 2D materials.
• High-speed manipulation of site-controlled quantum emitters (QEs) in 2D materials using SAWs is underexplored.

Purpose of the Study:

• To demonstrate acoustic manipulation of deterministic, strain-induced QEs in monolayer WSe2.
• To achieve high-speed optical modulation of QEs using SAWs.

Main Methods:

• Interfacing monolayer WSe2 with SAWs on a lithium niobate substrate.
• Using gold nanocube stressors to engineer local strain for deterministic QEs.
• Exciting QEs with SAWs and measuring energy shifts and modulation speeds.

Main Results:

• Deterministic QEs in WSe2 exhibited energy shifts up to 0.58 meV with an 8 MHz tuning bandwidth.
• Achieved half-GHz optical modulation speed for QEs located 210 nm above the substrate.
• Revealed a nonlinear response regime of the SAW-driven nanocube stressor.

Conclusions:

• Acoustic manipulation provides a robust and scalable approach for fast, dynamic tuning of single photons.
• The developed method offers suppressed spectral diffusion and potential for nanoscale quantum sensors.