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Abstract We explore the prospects and benefits of combining the techniques of cavity optomechanics with efforts to image spins using magnetic resonance force microscopy (MRFM). In particular, we focus on a common mechanical resonator used in cavity optomechanics—high-stress stoichiometric silicon nitride (Si3N4) membranes. We present experimental work with a ‘trampoline’ membrane resonator that has a quality factor above 106and an order of magnitude lower mass than a comparable standard membrane resonators. Such high-stress resonators are on a trajectory to reach 0.1 force sensitivities at MHz frequencies by using techniques such as soft clamping and phononic-crystal control of acoustic radiation in combination with cryogenic cooling. We present a demonstration of force-detected electron spin resonance of an ensemble at room temperature using the trampoline resonators functionalized with a magnetic grain. We discuss prospects for combining such a resonator with an integrated Fabry–Perot cavity readout at cryogenic temperatures, and provide ideas for future impacts of membrane cavity optomechanical devices on MRFM of nuclear spins.
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Focusing membrane metamirrors for integrated cavity optomechanics
Membrane-based cavity optomechanical systems have been widely successful; however, their chip-scale integration remains a significant challenge. Here we present a solution based on metasurface design. Specifically, by non-periodic photonic crystal patterning of a Si3N4membrane, we realize a suspended metamirror with a finite focal length, enabling formation of a stable optical cavity with a plane end-mirror. We present simulation, fabrication, and characterization of the metamirror using both free-space and cavity-based measurements, demonstrating reflectivities as high as 99% and cavity finesse as high as 600. The mirror radius of curvature (∼30cm) is inferred from the cavity mode spectrum. In combination with phononic engineering, focusing membrane mirrors offer a route towards high-cooperativity, vertically integrated cavity optomechanical systems with applications ranging from precision force sensing to hybrid quantum transduction.
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- Award ID(s):
- 2209473
- PAR ID:
- 10537115
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optica
- Volume:
- 11
- Issue:
- 9
- ISSN:
- 2334-2536
- Format(s):
- Medium: X Size: Article No. 1235
- Size(s):
- Article No. 1235
- Sponsoring Org:
- National Science Foundation
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