講演情報
[22p-A601-8]Coherence-based quantum sensing of low-frequency fields
〇Ernst David Herbschleb1, Izuru Ohki2, Kohki Morita1, Yoshiharu Yoshii3, Hiromitsu Kato4, Toshiharu Makino4, Satoshi Yamasaki5, Norikazu Mizuochi1 (1.Kyoto university, 2.QST, 3.Sumida Corporation, 4.AIST, 5.Kanazawa university)
キーワード：
quantum sensing、nitrogen-vacancy centre、nuclear magnetic resonance
Nitrogen-vacancy centres are considered suitable quantum sensors for example for medical applications, such as measuring nuclear magnetic resonance (NMR) spectra. Fourier-based algorithms have been implemented for measuring such NMR signals. However, they are limited to high frequencies signals (over 1 kHz) since dynamical decoupling sequences are applied. On the other hand, studying low-frequency signals is important for chemical structure analysis and for searching new particles beyond the standard model. In previous studies, optically detected magnetic resonance techniques were used to detect low-frequency signals. Here, we demonstrate a fitting-based algorithm to measure low-frequency fields with an over two orders of magnitude higher sensitivity, which is frequency independent in the low-frequency range. Besides in-depth simulation and measurement of the fundamental properties of our algorithm, we study the possibility to measure at ultra-low fields, essential for example for low-field NMR, as well. Finally, as proof-of-concept measurement, we detect low-frequency NMR signals, giving a narrow line width for the free nuclear precession of water of 1.6 Hz.