0000000000371416

AUTHOR

Kasper Jensen

0000-0002-8417-4328

showing 5 related works from this author

All-Optical Spin Locking in Alkali-Vapor Magnetometers

2018

The nonlinear Zeeman effect can induce splittings and asymmetries of magnetic-resonance lines in the geophysical magnetic-field range. We demonstrate a scheme to suppress the nonlinear Zeeman effect all optically based on spin locking. Spin locking is achieved with an effective oscillating magnetic field provided by the AC Stark-shift of an intensity-modulated and polarization-modulated laser beam. This results in the collapse of the multi-component asymmetric magnetic-resonance line with about 100 Hz width in the Earth-field range into a peak with a central component width of 25Hz. The technique is expected to be broadly applicable in practical magnetometry, potentially boosting the sensit…

Atomic Physics (physics.atom-ph)FOS: Physical sciencesPhysics - Atomic Physics
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Temperature- and Magnetic-Field-Dependent Longitudinal Spin Relaxation in Nitrogen-Vacancy Ensembles in Diamond

2011

We present an experimental study of the longitudinal electron-spin relaxation time (T1) of negatively charged nitrogen-vacancy (NV) ensembles in diamond. T1 was studied as a function of temperature from 5 to 475 K and magnetic field from 0 to 630 G for several samples with various NV and nitrogen concentrations. Our studies reveal three processes responsible for T1 relaxation. Above room temperature, a two-phonon Raman process dominates, and below, we observe an Orbach-type process with an activation energy, 73(4) meV, which closely matches the local vibrational modes of the NV center. At yet lower temperatures, sample dependent cross relaxation processes dominate, resulting in temperature …

Materials scienceNitrogenFOS: Physical sciencesGeneral Physics and Astronomy02 engineering and technologyActivation energyengineering.materialSpectrum Analysis Raman01 natural sciencessymbols.namesakeVacancy defect0103 physical sciences010306 general physicsCondensed Matter - Materials ScienceCondensed matter physicsTemperatureSpin–lattice relaxationMaterials Science (cond-mat.mtrl-sci)DiamondModels Theoretical021001 nanoscience & nanotechnologyMagnetic fieldMagnetic FieldsMolecular vibrationengineeringsymbolsDiamond0210 nano-technologyRaman spectroscopyOrder of magnitudePhysical Review Letters
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Magnetometry with Nitrogen-Vacancy Centers in Diamond

2016

This chapter covers magnetic sensing with nitrogen-vacancy (NV) defect centers in diamond. The NV center fundamentals are introduced and NV optically detected magnetic resonance techniques for dc and ac magnetic sensing are summarized. After reviewing some successful sensing applications, the advantages for using NV magnetometry, as well as some ongoing challenges, are enumerated.

Coherence timeMaterials scienceMagnetic noisebusiness.industrySensing applicationsMagnetometerDiamondchemistry.chemical_element02 engineering and technologyengineering.material021001 nanoscience & nanotechnology01 natural sciencesMagnetic sensingNitrogenlaw.inventionchemistrylawVacancy defect0103 physical sciencesengineeringOptoelectronics010306 general physics0210 nano-technologybusiness
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Sidebands in Optically Detected Magnetic Resonance Signals of Nitrogen Vacancy Centers in Diamond

2013

We study features in the optically detected magnetic resonance (ODMR) signals associated with negatively charged nitrogen-vacancy (NV) centers coupled to other paramagnetic impurities in diamond. Our results are important for understanding ODMR line shapes and for optimization of devices based on NV centers. We determine the origins of several side features to the unperturbed NV magnetic resonance by studying their magnetic field and microwave power dependences. Side resonances separated by around 130 MHz are due to hyperfine coupling between NV centers and nearest-neighbor C-13 nuclear spins. Side resonances separated by approximately {40, 260, 300} MHz are found to originate from simultan…

Atomic Physics (physics.atom-ph)chemistry.chemical_elementFOS: Physical sciences02 engineering and technologyengineering.material01 natural sciencesPhysics - Atomic PhysicsVacancy defect0103 physical sciences010306 general physicsSpin (physics)Line (formation)PhysicsQuantum PhysicsSpinsMicrowave powerDiamond021001 nanoscience & nanotechnologyCondensed Matter PhysicsNitrogen3. Good healthElectronic Optical and Magnetic MaterialsMagnetic fieldchemistryengineeringAtomic physics0210 nano-technologyQuantum Physics (quant-ph)
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Miniature Cavity-Enhanced Diamond Magnetometer

2017

We present a highly sensitive miniaturized cavity-enhanced room-temperature magnetic-field sensor based on nitrogen-vacancy (NV) centers in diamond. The magnetic resonance signal is detected by probing absorption on the 1042\,nm spin-singlet transition. To improve the absorptive signal the diamond is placed in an optical resonator. The device has a magnetic-field sensitivity of 28 pT/$\sqrt{\rm{Hz}}$, a projected photon shot-noise-limited sensitivity of 22 pT/$\sqrt{\rm{Hz}}$ and an estimated quantum projection-noise-limited sensitivity of 0.43 pT/$\sqrt{\rm{Hz}}$ with the sensing volume of $\sim$ 390 $\mu$m $\times$ 4500 $\mu$m$^{2}$. The presented miniaturized device is the basis for an e…

Physics - Instrumentation and DetectorsPhotonMaterials scienceMagnetometerGeneral Physics and AstronomyFOS: Physical sciences02 engineering and technologyengineering.material01 natural sciencesSignallaw.inventionlaw0103 physical sciencesMesoscale and Nanoscale Physics (cond-mat.mes-hall)[ PHYS.PHYS.PHYS-GEN-PH ] Physics [physics]/Physics [physics]/General Physics [physics.gen-ph][PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]010306 general physicsAbsorption (electromagnetic radiation)[ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]Quantum PhysicsCondensed Matter - Mesoscale and Nanoscale Physicsbusiness.industryDiamondInstrumentation and Detectors (physics.ins-det)021001 nanoscience & nanotechnology[PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph]Highly sensitiveOptical cavityengineeringOptoelectronics0210 nano-technologybusinessQuantum Physics (quant-ph)Sensitivity (electronics)
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