28 research outputs found
All-optical dc nanotesla magnetometry using silicon vacancy fine structure in isotopically purified silicon carbide
We uncover the fine structure of a silicon vacancy in isotopically purified
silicon carbide (4H-SiC) and find extra terms in the spin Hamiltonian,
originated from the trigonal pyramidal symmetry of this spin-3/2 color center.
These terms give rise to additional spin transitions, which are otherwise
forbidden, and lead to a level anticrossing in an external magnetic field. We
observe a sharp variation of the photoluminescence intensity in the vicinity of
this level anticrossing, which can be used for a purely all-optical sensing of
the magnetic field. We achieve dc magnetic field sensitivity of 87 nT
Hz within a volume of mm at room temperature
and demonstrate that this contactless method is robust at high temperatures up
to at least 500 K. As our approach does not require application of
radiofrequency fields, it is scalable to much larger volumes. For an optimized
light-trapping waveguide of 3 mm the projection noise limit is below 100
fT Hz.Comment: 12 pages, 6 figures; additional experimental data and an extended
theoretical analysis are added in the second versio
Defects in Nanodiamonds: Application of High-Frequency cw and Pulse EPR, ODMR
© 2014, Springer-Verlag Wien. Different aspects of applications of electron paramagnetic resonance (EPR) based techniques including high frequency (HF) electron spin echo (ESE), electron-nuclear double resonance (ENDOR) and optically detected magnetic resonance (ODMR) approaches to study diamond nanostructures are examined
Enormously high concentrations of fluorescent nitrogen-vacancy centers fabricated by sintering of detonation nanodiamonds
High-pressure, high-temperature sintering of detonation nanodiamonds is used to fabricate material containing high concentrations of nitrogen-vacancy (NV) centers, without post or prior irradiation of the samples. The concentration of the NV centers in the sintered nanodiamond clusters is up to 10 4 ppm (1%) and is three orders of magnitude higher than any reported so far. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Specific Features of a High-Frequency Electron Paramagnetic Resonance Spectrometer with Frequency Modulation
Defects in Nanodiamonds: Application of High-Frequency cw and Pulse EPR, ODMR
© 2014, Springer-Verlag Wien. Different aspects of applications of electron paramagnetic resonance (EPR) based techniques including high frequency (HF) electron spin echo (ESE), electron-nuclear double resonance (ENDOR) and optically detected magnetic resonance (ODMR) approaches to study diamond nanostructures are examined
Defects in Nanodiamonds: Application of High-Frequency cw and Pulse EPR, ODMR
© 2014, Springer-Verlag Wien. Different aspects of applications of electron paramagnetic resonance (EPR) based techniques including high frequency (HF) electron spin echo (ESE), electron-nuclear double resonance (ENDOR) and optically detected magnetic resonance (ODMR) approaches to study diamond nanostructures are examined
Defects in Nanodiamonds: Application of High-Frequency cw and Pulse EPR, ODMR
© 2014, Springer-Verlag Wien. Different aspects of applications of electron paramagnetic resonance (EPR) based techniques including high frequency (HF) electron spin echo (ESE), electron-nuclear double resonance (ENDOR) and optically detected magnetic resonance (ODMR) approaches to study diamond nanostructures are examined
All-optical quantum thermometry based on spin-level cross-relaxation and multicenter entanglement under ambient conditions in SiC
All-optical thermometry technique based on the energy level cross-relaxation in atomic-scale spin centers in SiC is demonstrated. This technique exploits a giant thermal shift of the zero-field splitting for centers in the triplet ground state, S=1, undetected by photoluminescence (so called âdarkâ centers) coupling to neighbouring spin-3/2 centers which can be optically polarized and read out (âbrightâ centers), and does not require radiofrequency fields. EPR was used to identify defects. The width of the cross-relaxation line is almost an order of magnitude smaller than the width of the excited state level-anticrossing line, which was used in all-optical thermometry and which can not be significantly reduced since determined by the lifetime of the excited state. With approximately the same temperature shift and the same signal intensities as for excited state level-anticrossing, cross-relaxation signal makes it possible to increase the sensitivity of the temperature measurement by more than an order of magnitude. Temperature sensitivity is estimated to be approximately 10 mK/Hz1/2 within a volume about 1 ÎŒ3, allocated by focused laser excitation in a scanning confocal microscope. Using cross-relaxation in the ground states of âbrightâ spin-3/2 centers and âdarkâ S=1 centers for temperature sensing and ground state level anti-crossing of âbrightâ spin-3/2 centers an integrated magnetic field and temperature sensor with submicron space resolution can be implemented using the same spin system. The coupling of individually addressable âbrightâ spin-3/2 centers connected by a chain of âdarkâ S=1 spins, could be considered in quantum information processing and multicenter entanglement under ambient conditions