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arXiv · 1805.10725

Highly sensitive macro-scale diamond magnetometer operated by dynamical decoupling sequence with coplanar waveguide resonator

Yuta Masuyama·Kousuke Mizuno·Hayato Ozawa·Hitoshi Ishiwata·Yuji Hatano·Takeshi Ohshima·Takayuki Iwasaki·Mutsuko Hatano
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Abstract

Ultimate sensitivity for quantum magnetometry using nitrogen-vacancy (NV) centers in diamond is limited by number of NV centers and coherence time. Microwave irradiation with a high and homogeneous power density for a large detection volume is necessary to achieve highly sensitive magnetometer. Here, we demonstrate a microwave resonator to enhance the power density of the microwave field and an optical system with a detection volume of 1.4e-3 mm$^3$. The strong microwave field enables us to achieve 48 ns Rabi oscillation which is sufficiently faster than the phase relaxation time of NV centers. This system combined with a decoupling pulse sequence, XY16, extends the spin coherence time (T2) up to 27 times longer than that with a spin echo method. Consequently, we obtained an AC magnetic field sensitivity of 10.8 pT/Hz$^{1/2}$ using the dynamical decoupling pulse sequence.

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Yuta Masuyama, Kousuke Mizuno, Hayato Ozawa, Hitoshi Ishiwata, Yuji Hatano, Takeshi Ohshima, Takayuki Iwasaki, Mutsuko Hatano. 2018-05-28. Highly sensitive macro-scale diamond magnetometer operated by dynamical decoupling sequence with coplanar waveguide resonator. https://doi.org/10.1063/1.5047078

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