Measurement of mutual gravitation on laboratory scales is an outstanding challenge and a prerequisite to probing theories of quantum gravity. A leading technology in tabletop gravity experiments is the torsion balance, with limitations due to thermal decoherence. Recent demonstrations of lithographically defined suspensions in thin-film silicon nitride with macroscale test masses suggest a path forward, as torsion pendulums dominated by gravitational stiffness may achieve higher mechanical quality factors through dilution of material losses. Here we demonstrate a 250 micron by 5 mm by 1.8 micron torsion fiber supporting 87 grams and forming a Cavendish-style torsion pendulum with tungsten test masses that -- to our knowledge -- is the largest thin-film silicon-nitride-based oscillator to date. Torsion pendulums with thin-film, nanofabricated suspensions provide a test bed for near-term tabletop experiments probing classical and quantum gravitational interaction between oscillators.
@article{arxiv.2601.11366,
title = {Nanofabricated torsion pendulums for tabletop gravity experiments},
author = {Jack Manley and Charles A. Condos and Zachary Fegley and Gayathrini Premawardhana and Thomas Bsaibes and Jacob M. Taylor and Dalziel J. Wilson and Jon R. Pratt},
journal= {arXiv preprint arXiv:2601.11366},
year = {2026}
}