We demonstrate electron spin polarization detection and electron paramagnetic resonance (EPR) spectroscopy using a direct current superconducting quantum interference device (dc-SQUID) magnetometer. Our target electron spin ensemble is directly glued on the dc-SQUID magnetometer that detects electron spin polarization induced by a external magnetic field or EPR in micrometer-sized area. The minimum distinguishable number of polarized spins and sensing volume of the electron spin polarization detection and the EPR spectroscopy are estimated to be ∼106 and ∼10−10cm3 (∼0.1 pl), respectively.
@article{arxiv.1511.04832,
title = {Electron paramagnetic resonance spectroscopy using a dc-SQUID magnetometer directly coupled to an electron spin ensemble},
author = {Hiraku Toida and Yuichiro Matsuzaki and Kosuke Kakuyanagi and Xiaobo Zhu and William J. Munro and Kae Nemoto and Hiroshi Yamaguchi and Shiro Saito},
journal= {arXiv preprint arXiv:1511.04832},
year = {2024}
}