Laser threshold magnetometry. (8th January 2016)

• Record Type: Journal Article
• Authors: Jeske, Jan; Cole, Jared H; Greentree, Andrew D
• Is Part Of: New journal of physics. Volume 18:Number 1(2016:Jan.)
• Publication Date: 2016-01-08
• Subjects: magnetometry -- nitrogen-vacancy centre -- lasing -- sensing; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/18/1/013015
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: We propose a new type of sensor, which uses diamond containing the optically active nitrogen-vacancy (NV − ) centres as a laser medium. The magnetometer can be operated at room-temperature and generates light that can be readily fibre coupled, thereby permitting use in industrial applications and remote sensing. By combining laser pumping with a radio-frequency Rabi-drive field, an external magnetic field changes the fluorescence of the NV − centres. We use this change in fluorescence level to push the laser above threshold, turning it on with an intensity controlled by the external magnetic field, which provides a coherent amplification of the readout signal with very high contrast. This mechanism is qualitatively different from conventional NV − –based magnetometers which use fluorescence measurements, based on incoherent photon emission. We term our approach laser threshold magnetometer (LTM). We predict that an NV − –based LTM with a volume of 1 mm 3 can achieve shot-noise limited dc sensitivity of 1.86 fT and ac sensitivity of 3.97 fT .