A new laboratory bound on the axial-vector mediated interaction between electron spins at micrometer scale is established with single nitrogen-vacancy (NV) centers in diamond. A single crystal of p-terphenyl doped pentacene-d14 under laser pumping provides the source of polarized electron spins. Based on the measurement of polarization signal via nitrogen-vacancy centers, we set a constraint for the exotic electron-electron coupling gAegAe, within the force range from 10 to 900 μm. The obtained upper bound of the coupling at 500 μm is ∣gAegAe/4πℏc∣≤1.8×10−19, which is one order of magnitude more stringent than a previous experiment. Our result shows that the NV center can be a promising platform for searching for new particles predicted by theories beyond the standard model.
@article{arxiv.1804.07026,
title = {Constraints on a Spin-Dependent Exotic Interaction between Electrons with Single Electron Spin Quantum Sensors},
author = {Xing Rong and Man Jiao and Jianpei Geng and Bo Zhang and Tianyu Xie and Fazhan Shi and Chang-Kui Duan and Yi-Fu Cai and Jiangfeng Du},
journal= {arXiv preprint arXiv:1804.07026},
year = {2018}
}