Radiation Pressure Backaction on a Hexagonal Boron Nitride Nanomechanical Resonator

Area of Science:

• Quantum optics
• Materials science
• Nanotechnology

Background:

• Hexagonal boron nitride (hBN) is a van der Waals material with exceptional mechanical properties.
• hBN hosts quantum emitters and spin defects sensitive to strain, crucial for quantum technologies.
• Optomechanical control of hBN is key for integrating spin degrees of freedom with cavity optomechanics.

Purpose of the Study:

• To report the first observation of radiation pressure backaction in a hBN mechanical resonator at telecom wavelengths.
• To demonstrate optomechanical coupling in a hBN drum-head resonator.
• To explore the potential for light-based tuning of hBN mechanical properties.

Main Methods:

• Fabrication of a hBN drum-head mechanical resonator.
• Integration of the hBN resonator into a high-finesse fiber-based Fabry-Pérot microcavity (membrane-in-the-middle configuration).
• Measurement of thermomechanical motion coupled to the optical cavity mode at telecom wavelengths.

Main Results:

• First observation of radiation pressure backaction in a hBN resonator at telecom wavelengths.
• Resolution of the optical spring effect and optomechanical damping.
• Achieved a single photon coupling strength of g0/2π = 1200 Hz.

Conclusions:

• Optomechanical control of hBN resonators is experimentally demonstrated.
• These findings enable hybrid quantum devices by combining hBN's spin properties with optomechanics.
• The study paves the way for light-tunable mechanical properties of hBN resonators.