Spin detection with a micromechanical trampoline: towards magnetic resonance microscopy harnessing cavity optomechanics
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$aN/Hz$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.

Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10304583
Journal Name:
New Journal of Physics
Volume:
21
Issue:
4
Page Range or eLocation-ID:
Article No. 043049
ISSN:
1367-2630
Publisher:
IOP Publishing
National Science Foundation
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