We present a "nanoladder" geometry that minimizes the mechanical dissipation of ultrasensitive cantilevers. A nanoladder cantilever consists of a lithographically patterned scaffold of rails and rungs with feature size ∼ 100 nm. Compared to a rectangular beam of the same dimensions, the mass and spring constant of a nanoladder are each reduced by roughly two orders of magnitude. We demonstrate a low force noise of 158(+62)(−42)zN and 190(+42)(−33)zN in a one-Hz bandwidth for devices made from silicon and diamond, respectively, measured at temperatures between 100--150 mK. As opposed to bottom-up mechanical resonators like nanowires or nanotubes, nanoladder cantilevers can be batch-fabricated using standard lithography, which is a critical factor for applications in scanning force microscopy.
@article{arxiv.1711.11358,
title = {Nanoladder cantilevers made from diamond and silicon},
author = {M. Héritier and A. Eichler and Y. Pan and U. Grob and I. Shorubalko and M. D. Krass and Y. Tao and C. L. Degen},
journal= {arXiv preprint arXiv:1711.11358},
year = {2018}
}