ORCID Profile
0000-0003-3328-9093
Current Organisations
University of Stuttgart
,
Max Planck Institute for Solid State Research
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Publisher: Springer Science and Business Media LLC
Date: 19-03-2013
DOI: 10.1038/NCOMMS2588
Abstract: The detection of small numbers of magnetic spins is a significant challenge in the life, physical and chemical sciences, especially when room temperature operation is required. Here we show that a proximal nitrogen-vacancy spin ensemble serves as a high precision sensing and imaging array. Monitoring its longitudinal relaxation enables sensing of freely diffusing, unperturbed magnetic ions and molecules in a microfluidic device without applying external magnetic fields. Multiplexed charge-coupled device acquisition and an optimized detection scheme permits direct spin noise imaging of magnetically labelled cellular structures under ambient conditions. Within 20 s we achieve spatial resolutions below 500 nm and experimental sensitivities down to 1,000 statistically polarized spins, of which only 32 ions contribute to a net magnetization. The results mark a major step towards versatile sub-cellular magnetic imaging and real-time spin sensing under physiological conditions providing a minimally invasive tool to monitor ion channels or haemoglobin trafficking inside live cells.
Publisher: Springer Science and Business Media LLC
Date: 08-05-2011
Abstract: Fluorescent particles are routinely used to probe biological processes. The quantum properties of single spins within fluorescent particles have been explored in the field of nanoscale magnetometry, but not yet in biological environments. Here, we demonstrate optically detected magnetic resonance of in idual fluorescent nanodiamond nitrogen-vacancy centres inside living human HeLa cells, and measure their location, orientation, spin levels and spin coherence times with nanoscale precision. Quantum coherence was measured through Rabi and spin-echo sequences over long (>10 h) periods, and orientation was tracked with effective 1° angular precision over acquisition times of 89 ms. The quantum spin levels served as fingerprints, allowing in idual centres with identical fluorescence to be identified and tracked simultaneously. Furthermore, monitoring decoherence rates in response to changes in the local environment may provide new information about intracellular processes. The experiments reported here demonstrate the viability of controlled single spin probes for nanomagnetometry in biological systems, opening up a host of new possibilities for quantum-based imaging in the life sciences.
Publisher: IEEE
Date: 08-2011
Publisher: American Association for the Advancement of Science (AAAS)
Date: 06-06-2008
Abstract: Robust entanglement at room temperature is a necessary requirement for practical applications in quantum technology. We demonstrate the creation of bipartite- and tripartite-entangled quantum states in a small quantum register consisting of in idual 13 C nuclei in a diamond lattice. In idual nuclear spins are controlled via their hyperfine coupling to a single electron at a nitrogen-vacancy defect center. Quantum correlations are of high quality and persist on a millisecond time scale even at room temperature, which is adequate for sophisticated quantum operations.
Publisher: Springer Science and Business Media LLC
Date: 30-11-2005
Publisher: IOP Publishing
Date: 17-11-2009
Publisher: Springer Science and Business Media LLC
Date: 18-12-2011
Abstract: Sensors based on the nitrogen-vacancy defect in diamond are being developed to measure weak magnetic and electric fields at the nanoscale. However, such sensors rely on measurements of a shift in the Lamor frequency of the defect, so an accumulation of quantum phase causes the measurement signal to exhibit a periodic modulation. This means that the measurement time is either restricted to half of one oscillation period, which limits accuracy, or that the magnetic field range must be known in advance. Moreover, the precision increases only slowly (as T(-0.5)) with measurement time T (ref. 3). Here, we implement a quantum phase estimation algorithm on a single nuclear spin in diamond to combine both high sensitivity and high dynamic range. By achieving a scaling of the precision with time to T(-0.85), we improve the sensitivity by a factor of 7.4 for an accessible field range of 16 mT, or, alternatively, we improve the dynamic range by a factor of 130 for a sensitivity of 2.5 µT Hz(-1/2). Quantum phase estimation algorithms have also recently been implemented using a single electron spin in a nitrogen-vacancy centre. These methods are applicable to a variety of field detection schemes, and do not require quantum entanglement.
Publisher: SPIE
Date: 09-02-2006
DOI: 10.1117/12.660186
Publisher: SPIE
Date: 08-02-2007
DOI: 10.1117/12.716391
Publisher: American Chemical Society (ACS)
Date: 19-03-2021
Publisher: American Chemical Society (ACS)
Date: 11-09-2017
DOI: 10.1021/ACS.NANOLETT.7B01796
Abstract: In recent years, solid-state spin systems have emerged as promising candidates for quantum information processing. Prominent ex les are the nitrogen-vacancy (NV) center in diamond, phosphorus dopants in silicon (Si:P), rare-earth ions in solids, and V
Publisher: American Physical Society (APS)
Date: 05-11-2004
Publisher: IOP Publishing
Date: 30-07-2004
Publisher: IOP Publishing
Date: 30-06-2014
Publisher: IOP Publishing
Date: 07-01-2009
Publisher: Springer Science and Business Media LLC
Date: 09-05-2012
DOI: 10.1038/SREP00401
Publisher: American Physical Society (APS)
Date: 23-08-2006
Publisher: American Physical Society (APS)
Date: 15-05-2012
Publisher: IOP Publishing
Date: 05-07-2011
Publisher: American Physical Society (APS)
Date: 31-08-2016
Publisher: AIP Publishing
Date: 09-01-2006
DOI: 10.1063/1.2158700
Abstract: Nitrogen-vacancy (NV−) color centers in diamond were created by implantation of 7 keV N15(I=1∕2) ions into type IIa diamond. Optically detected magnetic resonance was employed to measure the hyperfine coupling of single NV− centers. The hyperfine spectrum from NV−15 arising from implanted N15 can be distinguished from NV−14 centers created by native N14(I=1) sites. Analysis indicates 1 in 40 implanted N15 atoms give rise to an optically observable NV−15 center. This report ultimately demonstrates a mechanism by which the yield of NV− center formation by nitrogen implantation can be measured.
Publisher: American Physical Society (APS)
Date: 14-05-2009
Publisher: American Physical Society (APS)
Date: 13-12-2006
Publisher: IOP Publishing
Date: 06-03-2006
Publisher: American Physical Society (APS)
Date: 21-02-2008
Publisher: American Physical Society (APS)
Date: 02-02-2011
Publisher: American Physical Society (APS)
Date: 28-07-2019
Publisher: IOP Publishing
Date: 23-07-2013
Publisher: AIP Publishing
Date: 10-03-2014
DOI: 10.1063/1.4868128
Abstract: Synthetic diamond production is a key to the development of quantum metrology and quantum information applications of diamond. The major quantum sensor and qubit candidate in diamond is the nitrogen-vacancy (NV) color center. This lattice defect comes in four different crystallographic orientations leading to an intrinsic inhomogeneity among NV centers, which is undesirable in some applications. Here, we report a microwave plasma-assisted chemical vapor deposition diamond growth technique on (111)-oriented substrates, which yields perfect alignment (94% ± 2%) of as-grown NV centers along a single crystallographic direction. In addition, clear evidence is found that the majority (74% ± 4%) of the aligned NV centers were formed by the nitrogen being first included in the (111) growth surface and then followed by the formation of a neighboring vacancy on top. The achieved homogeneity of the grown NV centers will tremendously benefit quantum information and metrology applications.
Publisher: Wiley
Date: 11-2015
Publisher: Springer Science and Business Media LLC
Date: 28-02-2010
DOI: 10.1038/NPHYS1536
Publisher: American Chemical Society (ACS)
Date: 18-04-2022
Publisher: AIP Publishing
Date: 21-12-2005
DOI: 10.1063/1.2103389
Abstract: Single defect centers in diamond have been generated via nitrogen implantation. The defects have been investigated by single defect center fluorescence microscopy. Optical and electron paramagnetic resonance spectra unambiguously show that the produced defect is the nitrogen-vacancy color center. An analysis of the nitrogen flux together with a determination of the number of nitrogen-vacancy centers yields that on average one 2MeV nitrogen atom need to be implanted per defect center.
Publisher: American Chemical Society (ACS)
Date: 12-12-2016
Publisher: Elsevier BV
Date: 07-2011
Publisher: Pleiades Publishing Ltd
Date: 2005
DOI: 10.1134/1.2034610
Publisher: American Physical Society (APS)
Date: 20-02-2004
Publisher: Wiley
Date: 21-10-2015
Publisher: Elsevier BV
Date: 07-2013
Publisher: AIP Publishing
Date: 25-03-2005
DOI: 10.1063/1.1896088
Abstract: Fabrication of single nickel-nitrogen (NE8) defect centers in diamond by chemical vapor deposition is demonstrated. Under continuous-wave 745nm laser excitation single defects were induced to emit single photon pulses at 797nm with a linewidth of 1.5nm at room temperature. Photon antibunching of single centers was demonstrated using a Hanbury–Brown and Twiss interferometer. Confocal images revealed approximately 106 optically active sites∕cm2 in the synthesized films. The controlled fabrication of an NE8 based single photon source in synthetic diamond is important for fiber based quantum cryptography, and potentially linear optics quantum computing.
Publisher: Springer Science and Business Media LLC
Date: 17-04-2011
DOI: 10.1038/NPHYS1969
Publisher: American Physical Society (APS)
Date: 03-03-2014
Publisher: American Physical Society (APS)
Date: 27-06-2013
Publisher: SPIE-Intl Soc Optical Eng
Date: 06-08-2020
Publisher: Springer Science and Business Media LLC
Date: 28-05-2006
DOI: 10.1038/NPHYS318
Publisher: Springer Science and Business Media LLC
Date: 13-09-2005
Publisher: American Physical Society (APS)
Date: 03-05-2012
Publisher: American Physical Society (APS)
Date: 20-09-2004
Publisher: American Chemical Society (ACS)
Date: 20-04-2022
Publisher: Springer Science and Business Media LLC
Date: 23-06-2013
Abstract: Electron and nuclear spins associated with point defects in insulators are promising systems for solid-state quantum technology. The electron spin is usually used for readout and addressing, and nuclear spins are used as exquisite quantum bits and memory systems. With these systems, single-shot readout of single nuclear spins as well as entanglement, aided by the electron spin, have been shown. Although the electron spin in this ex le is essential for readout, it usually limits the nuclear spin coherence, leading to a quest for defects with spin-free ground states. Here, we isolate a hitherto unidentified defect in diamond and use it at room temperature to demonstrate optical spin polarization and readout with exceptionally high contrast (up to 45%), coherent manipulation of an in idual excited triplet state spin, and coherent nuclear spin manipulation using the triplet electron spin as a metastable ancilla. We demonstrate nuclear magnetic resonance and Rabi oscillations of the uncoupled nuclear spin in the spin-free electronic ground state. Our study demonstrates that nuclei coupled to single metastable electron spins are useful quantum systems with long memory times, in spite of electronic relaxation processes.
Publisher: Proceedings of the National Academy of Sciences
Date: 17-06-2013
Abstract: Magnetic field fluctuations arising from fundamental spins are ubiquitous in nanoscale biology, and are a rich source of information about the processes that generate them. However, the ability to detect the few spins involved without averaging over large ensembles has remained elusive. Here, we demonstrate the detection of gadolinium spin labels in an artificial cell membrane under ambient conditions using a single-spin nanodiamond sensor. Changes in the spin relaxation time of the sensor located in the lipid bilayer were optically detected and found to be sensitive to near-in idual (4 ± 2) proximal gadolinium atomic labels. The detection of such small numbers of spins in a model biological setting, with projected detection times of 1 s [corresponding to a sensitivity of ∼5 Gd spins per Hz 1/2 ], opens a pathway for in situ nanoscale detection of dynamical processes in biology.
Publisher: IOP Publishing
Date: 30-04-2008
Publisher: American Chemical Society (ACS)
Date: 29-09-2007
DOI: 10.1021/NL0719271
Abstract: Nanodiamond crystals containing single color centers have been grown by chemical vapor deposition (CVD). The fluorescence from in idual crystallites was directly correlated with crystallite size using a combined atomic force and scanning confocal fluorescence microscope. Under the conditions employed, the optimal size for single optically active nitrogen-vacancy (NV) center incorporation was measured to be 60-70 nm. The findings highlight a strong dependence of NV incorporation on crystal size, particularly with crystals less than 50 nm in size.
Publisher: OSA
Date: 2017
No related grants have been discovered for Joerg Wrachtrup.