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SIMIT makes important progress in miniature optoelectronic integrated diamond quantum magnetic sensor
Post Date: 13 May 2022 Viewed: 459
Recently, the State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), has prepared a miniature optoelectronic integrated diamond quantum magnetic sensor based on nitrogen-vacancy (NV) centers using micro and nano processing technology.
On May 9, the research results were published in Applied Physics Letters under the title A microfabricated fiber-integrated diamond magnetometer with ensemble nitrogen-vacancy centers.
Diamonds, not only can be used as jewelry accessories, but also are new quantum materials with high research value. Nitrogen-vacancy defects - NV centers, the most common point defects in diamond crystal structure, are formed by replacing carbon atoms and adjacent cavities by nitrogen atoms, and their quantum paramagnetic resonance effects in magnetic fields and fluorescence radiation properties can be used for precision magnetic measurements.
NV centers also have stable quantum states at room temperature and can work at uncooled room temperature. Meanwhile, with its technical advantages of high spatial resolution, high sensitivity, and high biocompatibility, the diamond quantum magnetic sensor has important application prospects in the fields of near-field microscopic magnetic resonance, magnetic anomaly detection, and life sciences.
ABSTRACT
Miniaturization is a trend of development toward practical applications for diamond nitrogen-vacancy centers-based sensors. We demonstrate a compact diamond magnetic field sensor device using a standard microfabrication process. A single-crystal-diamond plate is embedded in a cavity formed with stacking of three silicon chips. Thermal compression bonding is implemented at silicon–silicon and diamond–silicon interfaces ensuring mechanical robustness. The specific construction volume for the essential sensor component is about 10 × 10 × 1.5 mm3. By integrating a gradient index lens pigtailed fiber to the sensor device, 532-nm laser light and emitted fluorescence share a common path for excitation and detection. An omega-shaped transmission line for applied microwave power is fabricated directly on the surface of diamond. The integrated sensor device exhibits an optimized sensitivity of 2.03 nT·Hz−1/2 and over twofold enhancement of fluorescence collection efficiency compared to bare diamond. Such a sensor is utilized to measure a magnetic field change caused by switching a household electrical appliance.
More information: 10.1063/5.0089732
