Nitrogen-vacancy centers in diamond are attractive as quantum sensors owing to their remarkable optical and spin properties under ambient conditions. Here we experimentally demonstrated a hybrid fiber-based thermometer coupled with nitrogen-vacancy center ensemble and a permanent magnet, where the temperature sensitivity was improved by converting the temperature variation to the magnetic field change based on the thermal-demagnetization of the permanent magnet. We have achieved both large temperature working range (room temperature to 373 K) and millikelvin sensitivity (1.6 mK/sqrt(Hz)), nearly 6-fold improvement compared with conventional technique. This stable and compact hybrid thermometer will enable a wide range of applications for large-area detection and imaging with high temperature sensitivity.
@article{arxiv.1907.11309,
title = {Thermal-demagnetization-enhanced hybrid fiber-based thermometer coupled with nitrogen-vacancy centers},
author = {Shao-Chun Zhang and Shen Li and Bo Du and Yang Dong and Yu Zheng and Hao-Bin Lin and Bo-Wen Zhao and Wei Zhu and Guan-Zhong Wang and Xiang-Dong Chen and Guang-Can Guo and Fang-Wen Sun},
journal= {arXiv preprint arXiv:1907.11309},
year = {2019}
}