Diamond quantum magnetometer with dc sensitivity of < 10 pT Hz${}^{-1/2}$ toward measurement of biomagnetic field

Abstract

We present a sensitive diamond quantum sensor with a magnetic field sensitivity of $9.4\pm 0.1pT/\sqrt{\mathrm{Hz}}$ in a near-dc frequency range of 5 to 100~Hz. This sensor is based on the continuous-wave optically detected magnetic resonance of an ensemble of nitrogen-vacancy centers along the [111] direction in a diamond (111) single crystal. The long $T_2^{\ast }\sim 2\mu \mathrm{s}$ in our diamond and the reduced intensity noise in laser-induced fluorescence result in remarkable sensitivity among diamond quantum sensors. Based on an Allan deviation analysis, we demonstrate that a sub-picotesla field of 0.3~pT is detectable by interrogating the magnetic field for a few thousand seconds. The sensor head is compatible with various practical applications and allows a minimum measurement distance of about 1~mm from the sensing region. The proposed sensor facilitates the practical application of diamond quantum sensors.

8 pages, 5 figures

References in corpus (3)

• High-sensitivity diamond magnetometer with nanoscale resolution
• Fiber-coupled Diamond Magnetometry with an Unshielded 30 pT/$\sqrt{\text{Hz}}$ Sensitivity
• Nuclear quadrupole resonance spectroscopy with a femtotesla diamond magnetometer

Cited by in corpus (5)

• The impact of microwave phase noise on diamond quantum sensing
• Performance Evaluation of a Diamond Quantum Magnetometer for Biomagnetic Sensing: A Phantom Study
• High-Fidelity Entangling Gates for Electron and Nuclear Spin Qubits in Diamond
• Miniaturized magnetic-field sensor based on nitrogen-vacancy centers
• Suppression of coherent errors during entangling operations in NV centers in diamond