Coupling graphene mechanical resonators to superconducting microwave cavities

Area of Science:

• Nanotechnology
• Quantum Physics
• Materials Science

Background:

• Graphene offers exceptional properties for nanomechanical devices, including high frequencies, quality factors, and low mass.
• A key challenge is achieving strong coupling between graphene motion and external systems for efficient signal readout and manipulation.

Purpose of the Study:

• To develop a novel method for coupling graphene mechanical resonators to superconducting microwave cavities.
• To demonstrate electrostatic tunability of the coupling strength and mechanical properties.

Main Methods:

• Capacitive coupling of a high-quality factor (Q ≈ 10^5) graphene mechanical resonator to a superconducting microwave cavity.
• Electrostatic tuning of the graphene resonator's equilibrium position.

Main Results:

• Achieved a large single-photon coupling of approximately 10 Hz.
• Demonstrated electrostatic control over single-photon coupling, mechanical resonance frequency, and Duffing nonlinearity.
• Showcased strong tunability of optomechanical coupling strength on a fast time scale.

Conclusions:

• The novel coupling approach significantly enhances control over graphene-based nanomechanical systems.
• The demonstrated tunability paves the way for exploring quantum optomechanics with graphene resonators.
• Further improvements could enable entry into the quantum optomechanics regime.