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Dovzhenko Y, Casola F, Schlotter S, Zhou TX, Büttner F, Walsworth RL, Beach GSD, Yacoby A. Magnetostatic twists in room-temperature skyrmions explored by nitrogen-vacancy center spin texture reconstruction. Nat Commun 2018; 9:2712. [PMID: 30006532 PMCID: PMC6045603 DOI: 10.1038/s41467-018-05158-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 05/01/2018] [Indexed: 11/27/2022] Open
Abstract
Magnetic skyrmions are two-dimensional non-collinear spin textures characterized by an integer topological number. Room-temperature skyrmions were recently found in magnetic multilayer stacks, where their stability was largely attributed to the interfacial Dzyaloshinskii-Moriya interaction. The strength of this interaction and its role in stabilizing the skyrmions is not yet well understood, and imaging of the full spin structure is needed to address this question. Here, we use a nitrogen-vacancy centre in diamond to measure a map of magnetic fields produced by a skyrmion in a magnetic multilayer under ambient conditions. We compute the manifold of candidate spin structures and select the physically meaningful solution. We find a Néel-type skyrmion whose chirality is not left-handed, contrary to preceding reports. We propose skyrmion tube-like structures whose chirality rotates through the film thickness. We show that NV magnetometry, combined with our analysis method, provides a unique tool to investigate this previously inaccessible phenomenon.
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Affiliation(s)
- Y Dovzhenko
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, MA, 02138, USA
| | - F Casola
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, MA, 02138, USA
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA, 02138, USA
| | - S Schlotter
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - T X Zhou
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, MA, 02138, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - F Büttner
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - R L Walsworth
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, MA, 02138, USA
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA, 02138, USA
| | - G S D Beach
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - A Yacoby
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, MA, 02138, USA.
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2
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Rosenfeld EL, Pham LM, Lukin MD, Walsworth RL. Sensing Coherent Dynamics of Electronic Spin Clusters in Solids. Phys Rev Lett 2018; 120:243604. [PMID: 29956999 DOI: 10.1103/physrevlett.120.243604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Indexed: 06/08/2023]
Abstract
We observe coherent spin exchange between identical electronic spins in the solid state, a key step towards full quantum control of electronic spin registers in room temperature solids. In a diamond substrate, a single nitrogen vacancy (NV) center coherently couples to two adjacent S=1/2 dark electron spins via the magnetic dipolar interaction. We quantify NV-electron and electron-electron couplings via detailed spectroscopy, with good agreement to a model of strongly interacting spins. The electron-electron coupling enables an observation of coherent flip-flop dynamics between electronic spins in the solid state, which occur conditionally on the state of the NV. Finally, as a demonstration of coherent control, we selectively couple and transfer polarization between the NV and the pair of electron spins. Our observations enable the realization of fast quantum gate operations and quantum state transfer in a scalable, room temperature, quantum processor.
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Affiliation(s)
- E L Rosenfeld
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - L M Pham
- MIT Lincoln Laboratory, Lexington, Massachusetts 02421, USA
| | - M D Lukin
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - R L Walsworth
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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3
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Lovchinsky I, Sushkov AO, Urbach E, de Leon NP, Choi S, De Greve K, Evans R, Gertner R, Bersin E, Müller C, McGuinness L, Jelezko F, Walsworth RL, Park H, Lukin MD. Nuclear magnetic resonance detection and spectroscopy of single proteins using quantum logic. Science 2016; 351:836-41. [DOI: 10.1126/science.aad8022] [Citation(s) in RCA: 301] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 01/21/2016] [Indexed: 02/05/2023]
Affiliation(s)
- I. Lovchinsky
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - A. O. Sushkov
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - E. Urbach
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - N. P. de Leon
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - S. Choi
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - K. De Greve
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - R. Evans
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - R. Gertner
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - E. Bersin
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
| | - C. Müller
- Institute for Quantum Optics and Center for Integrated Quantum Science and Technology (IQST), Ulm University, D-89081, Ulm, Germany
| | - L. McGuinness
- Institute for Quantum Optics and Center for Integrated Quantum Science and Technology (IQST), Ulm University, D-89081, Ulm, Germany
| | - F. Jelezko
- Institute for Quantum Optics and Center for Integrated Quantum Science and Technology (IQST), Ulm University, D-89081, Ulm, Germany
| | - R. L. Walsworth
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA
- Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
| | - H. Park
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
- Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
- Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - M. D. Lukin
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
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4
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Arai K, Belthangady C, Zhang H, Bar-Gill N, DeVience SJ, Cappellaro P, Yacoby A, Walsworth RL. Fourier magnetic imaging with nanoscale resolution and compressed sensing speed-up using electronic spins in diamond. Nat Nanotechnol 2015; 10:859-864. [PMID: 26258549 DOI: 10.1038/nnano.2015.171] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 07/03/2015] [Indexed: 06/04/2023]
Abstract
Optically detected magnetic resonance using nitrogen-vacancy (NV) colour centres in diamond is a leading modality for nanoscale magnetic field imaging, as it provides single electron spin sensitivity, three-dimensional resolution better than 1 nm (ref. 5) and applicability to a wide range of physical and biological samples under ambient conditions. To date, however, NV-diamond magnetic imaging has been performed using 'real-space' techniques, which are either limited by optical diffraction to ∼250 nm resolution or require slow, point-by-point scanning for nanoscale resolution, for example, using an atomic force microscope, magnetic tip, or super-resolution optical imaging. Here, we introduce an alternative technique of Fourier magnetic imaging using NV-diamond. In analogy with conventional magnetic resonance imaging (MRI), we employ pulsed magnetic field gradients to phase-encode spatial information on NV electronic spins in wavenumber or 'k-space' followed by a fast Fourier transform to yield real-space images with nanoscale resolution, wide field of view and compressed sensing speed-up.
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Affiliation(s)
- K Arai
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C Belthangady
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - H Zhang
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - N Bar-Gill
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - S J DeVience
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - P Cappellaro
- Nuclear Science and Engineering Department, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A Yacoby
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - R L Walsworth
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138, USA
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5
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Glenn DR, Lee K, Park H, Weissleder R, Yacoby A, Lukin MD, Lee H, Walsworth RL, Connolly CB. Single-cell magnetic imaging using a quantum diamond microscope. Nat Methods 2015; 12:736-738. [PMID: 26098019 PMCID: PMC4521973 DOI: 10.1038/nmeth.3449] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 05/14/2015] [Indexed: 11/09/2022]
Abstract
We apply a quantum diamond microscope for detection and imaging of immunomagnetically labeled cells. This instrument uses nitrogen-vacancy (NV) centers in diamond for correlated magnetic and fluorescence imaging. Our device provides single-cell resolution and a field of view (∼1 mm(2)) two orders of magnitude larger than that of previous NV imaging technologies, enabling practical applications. To illustrate, we quantified cancer biomarkers expressed by rare tumor cells in a large population of healthy cells.
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Affiliation(s)
- D R Glenn
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA
| | - K Lee
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - H Park
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, USA
- Center for Brain Science, Harvard University, Cambridge, Massachusetts, USA
| | - R Weissleder
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - A Yacoby
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
| | - M D Lukin
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
| | - H Lee
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - R L Walsworth
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA
- Department of Physics, Harvard University, Cambridge, Massachusetts, USA
- Center for Brain Science, Harvard University, Cambridge, Massachusetts, USA
| | - C B Connolly
- Quantum Diamond Technologies, Inc., Somerville, MA, USA
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6
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Sushkov AO, Chisholm N, Lovchinsky I, Kubo M, Lo PK, Bennett SD, Hunger D, Akimov A, Walsworth RL, Park H, Lukin MD. All-optical sensing of a single-molecule electron spin. Nano Lett 2014; 14:6443-6448. [PMID: 25333198 DOI: 10.1021/nl502988n] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate an all-optical method for magnetic sensing of individual molecules in ambient conditions at room temperature. Our approach is based on shallow nitrogen-vacancy (NV) centers near the surface of a diamond crystal, which we use to detect single paramagnetic molecules covalently attached to the diamond surface. The manipulation and readout of the NV centers is all-optical and provides a sensitive probe of the magnetic field fluctuations stemming from the dynamics of the electronic spins of the attached molecules. As a specific example, we demonstrate detection of a single paramagnetic molecule containing a gadolinium (Gd(3+)) ion. We confirm single-molecule resolution using optical fluorescence and atomic force microscopy to colocalize one NV center and one Gd(3+)-containing molecule. Possible applications include nanoscale and in vivo magnetic spectroscopy and imaging of individual molecules.
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Affiliation(s)
- A O Sushkov
- Department of Physics, ‡Department of Chemistry and Chemical Biology, §School of Engineering and Applied Sciences, Harvard University , Cambridge, Massachusetts 02138, United States
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7
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Sushkov AO, Lovchinsky I, Chisholm N, Walsworth RL, Park H, Lukin MD. Magnetic resonance detection of individual proton spins using quantum reporters. Phys Rev Lett 2014; 113:197601. [PMID: 25415924 DOI: 10.1103/physrevlett.113.197601] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Indexed: 06/04/2023]
Abstract
We demonstrate a method of magnetic resonance imaging with single nuclear-spin sensitivity under ambient conditions. Our method employs isolated electronic-spin quantum bits (qubits) as magnetic resonance "reporters" on the surface of high purity diamond. These spin qubits are localized with nanometer-scale uncertainty, and their quantum state is coherently manipulated and measured optically via a proximal nitrogen-vacancy color center located a few nanometers below the diamond surface. This system is then used for sensing, coherent coupling, and imaging of individual proton spins on the diamond surface with angstrom resolution. Our approach may enable direct structural imaging of complex molecules that cannot be accessed from bulk studies. It realizes a new platform for probing novel materials, monitoring chemical reactions, and manipulation of complex systems on surfaces at a quantum level.
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Affiliation(s)
- A O Sushkov
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA and Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - I Lovchinsky
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - N Chisholm
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - R L Walsworth
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA and Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA and Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138, USA
| | - H Park
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA and Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA and Broad Institute of MIT and Harvard, 7 Cambridge Center, Cambridge, Massachusetts 02142, USA
| | - M D Lukin
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
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8
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Grinolds MS, Warner M, De Greve K, Dovzhenko Y, Thiel L, Walsworth RL, Hong S, Maletinsky P, Yacoby A. Subnanometre resolution in three-dimensional magnetic resonance imaging of individual dark spins. Nat Nanotechnol 2014; 9:279-284. [PMID: 24658168 DOI: 10.1038/nnano.2014.30] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 01/27/2014] [Indexed: 06/03/2023]
Abstract
Magnetic resonance imaging (MRI) has revolutionized biomedical science by providing non-invasive, three-dimensional biological imaging. However, spatial resolution in conventional MRI systems is limited to tens of micrometres, which is insufficient for imaging on molecular scales. Here, we demonstrate an MRI technique that provides subnanometre spatial resolution in three dimensions, with single electron-spin sensitivity. Our imaging method works under ambient conditions and can measure ubiquitous 'dark' spins, which constitute nearly all spin targets of interest. In this technique, the magnetic quantum-projection noise of dark spins is measured using a single nitrogen-vacancy (NV) magnetometer located near the surface of a diamond chip. The distribution of spins surrounding the NV magnetometer is imaged with a scanning magnetic-field gradient. To evaluate the performance of the NV-MRI technique, we image the three-dimensional landscape of electronic spins at the diamond surface and achieve an unprecedented combination of resolution (0.8 nm laterally and 1.5 nm vertically) and single-spin sensitivity. Our measurements uncover electronic spins on the diamond surface that can potentially be used as resources for improved magnetic imaging. This NV-MRI technique is immediately applicable to diverse systems including imaging spin chains, readout of spin-based quantum bits, and determining the location of spin labels in biological systems.
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Affiliation(s)
- M S Grinolds
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - M Warner
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - K De Greve
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - Y Dovzhenko
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - L Thiel
- 1] Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA [2] Department of Physics, University of Basel, Klingelbergstrasse 82, Basel, CH-4056 Switzerland
| | - R L Walsworth
- 1] Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA [2] Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA
| | - S Hong
- Vienna Center for Quantum Science and Technology (VCQ), Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - P Maletinsky
- Department of Physics, University of Basel, Klingelbergstrasse 82, Basel, CH-4056 Switzerland
| | - A Yacoby
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
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9
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Le Sage D, Arai K, Glenn DR, DeVience SJ, Pham LM, Rahn-Lee L, Lukin MD, Yacoby A, Komeili A, Walsworth RL. Optical magnetic imaging of living cells. Nature 2013; 496:486-9. [PMID: 23619694 PMCID: PMC3641584 DOI: 10.1038/nature12072] [Citation(s) in RCA: 218] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 03/14/2013] [Indexed: 11/09/2022]
Abstract
Magnetic imaging is a powerful tool for probing biological and physical systems. However, existing techniques either have poor spatial resolution compared to optical microscopy and are hence not generally applicable to imaging of sub-cellular structure (for example, magnetic resonance imaging), or entail operating conditions that preclude application to living biological samples while providing submicrometre resolution (for example, scanning superconducting quantum interference device microscopy, electron holography and magnetic resonance force microscopy). Here we demonstrate magnetic imaging of living cells (magnetotactic bacteria) under ambient laboratory conditions and with sub-cellular spatial resolution (400 nanometres), using an optically detected magnetic field imaging array consisting of a nanometre-scale layer of nitrogen-vacancy colour centres implanted at the surface of a diamond chip. With the bacteria placed on the diamond surface, we optically probe the nitrogen-vacancy quantum spin states and rapidly reconstruct images of the vector components of the magnetic field created by chains of magnetic nanoparticles (magnetosomes) produced in the bacteria. We also spatially correlate these magnetic field maps with optical images acquired in the same apparatus. Wide-field microscopy allows parallel optical and magnetic imaging of multiple cells in a population with submicrometre resolution and a field of view in excess of 100 micrometres. Scanning electron microscope images of the bacteria confirm that the correlated optical and magnetic images can be used to locate and characterize the magnetosomes in each bacterium. Our results provide a new capability for imaging bio-magnetic structures in living cells under ambient conditions with high spatial resolution, and will enable the mapping of a wide range of magnetic signals within cells and cellular networks.
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Affiliation(s)
- D Le Sage
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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10
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Belthangady C, Bar-Gill N, Pham LM, Arai K, Le Sage D, Cappellaro P, Walsworth RL. Dressed-state resonant coupling between bright and dark spins in diamond. Phys Rev Lett 2013; 110:157601. [PMID: 25167312 DOI: 10.1103/physrevlett.110.157601] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Indexed: 06/03/2023]
Abstract
Under ambient conditions, spin impurities in solid-state systems are found in thermally mixed states and are optically "dark"; i.e., the spin states cannot be optically controlled. Nitrogen-vacancy (NV) centers in diamond are an exception in that the electronic spin states are "bright"; i.e., they can be polarized by optical pumping, coherently manipulated with spin-resonance techniques, and read out optically, all at room temperature. Here we demonstrate a scheme to resonantly couple bright NV electronic spins to dark substitutional-nitrogen (P1) electronic spins by dressing their spin states with oscillating magnetic fields. This resonant coupling mechanism can be used to transfer spin polarization from NV spins to nearby dark spins and could be used to cool a mesoscopic bath of dark spins to near-zero temperature, thus providing a resource for quantum information and sensing, and aiding studies of quantum effects in many-body spin systems.
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Affiliation(s)
- C Belthangady
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - N Bar-Gill
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - L M Pham
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - K Arai
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - D Le Sage
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - P Cappellaro
- Nuclear Science and Engineering Department, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - R L Walsworth
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
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11
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Glenn DR, Zhang H, Kasthuri N, Schalek R, Lo PK, Trifonov AS, Park H, Lichtman JW, Walsworth RL. Correlative light and electron microscopy using cathodoluminescence from nanoparticles with distinguishable colours. Sci Rep 2012; 2:865. [PMID: 23155483 PMCID: PMC3498735 DOI: 10.1038/srep00865] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 10/23/2012] [Indexed: 11/09/2022] Open
Abstract
Correlative light and electron microscopy promises to combine molecular specificity with nanoscale imaging resolution. However, there are substantial technical challenges including reliable co-registration of optical and electron images, and rapid optical signal degradation under electron beam irradiation. Here, we introduce a new approach to solve these problems: imaging of stable optical cathodoluminescence emitted in a scanning electron microscope by nanoparticles with controllable surface chemistry. We demonstrate well-correlated cathodoluminescence and secondary electron images using three species of semiconductor nanoparticles that contain defects providing stable, spectrally-distinguishable cathodoluminescence. We also demonstrate reliable surface functionalization of the particles. The results pave the way for the use of such nanoparticles for targeted labeling of surfaces to provide nanoscale mapping of molecular composition, indicated by cathodoluminescence colour, simultaneously acquired with structural electron images in a single instrument.
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Affiliation(s)
- D R Glenn
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA
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12
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Maletinsky P, Hong S, Grinolds MS, Hausmann B, Lukin MD, Walsworth RL, Loncar M, Yacoby A. A robust scanning diamond sensor for nanoscale imaging with single nitrogen-vacancy centres. Nat Nanotechnol 2012; 7:320-4. [PMID: 22504708 DOI: 10.1038/nnano.2012.50] [Citation(s) in RCA: 187] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 03/13/2012] [Indexed: 05/05/2023]
Abstract
The nitrogen-vacancy defect centre in diamond has potential applications in nanoscale electric and magnetic-field sensing, single-photon microscopy, quantum information processing and bioimaging. These applications rely on the ability to position a single nitrogen-vacancy centre within a few nanometres of a sample, and then scan it across the sample surface, while preserving the centre's spin coherence and readout fidelity. However, existing scanning techniques, which use a single diamond nanocrystal grafted onto the tip of a scanning probe microscope, suffer from short spin coherence times due to poor crystal quality, and from inefficient far-field collection of the fluorescence from the nitrogen-vacancy centre. Here, we demonstrate a robust method for scanning a single nitrogen-vacancy centre within tens of nanometres from a sample surface that addresses both of these concerns. This is achieved by positioning a single nitrogen-vacancy centre at the end of a high-purity diamond nanopillar, which we use as the tip of an atomic force microscope. Our approach ensures long nitrogen-vacancy spin coherence times (∼75 µs), enhanced nitrogen-vacancy collection efficiencies due to waveguiding, and mechanical robustness of the device (several weeks of scanning time). We are able to image magnetic domains with widths of 25 nm, and demonstrate a magnetic field sensitivity of 56 nT Hz(-1/2) at a frequency of 33 kHz, which is unprecedented for scanning nitrogen-vacancy centres.
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Affiliation(s)
- P Maletinsky
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
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13
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Jiang L, Hodges JS, Maze JR, Maurer P, Taylor JM, Cory DG, Hemmer PR, Walsworth RL, Yacoby A, Zibrov AS, Lukin MD. Repetitive readout of a single electronic spin via quantum logic with nuclear spin ancillae. Science 2009; 326:267-72. [PMID: 19745117 DOI: 10.1126/science.1176496] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Robust measurement of single quantum bits plays a key role in the realization of quantum computation and communication as well as in quantum metrology and sensing. We have implemented a method for the improved readout of single electronic spin qubits in solid-state systems. The method makes use of quantum logic operations on a system consisting of a single electronic spin and several proximal nuclear spin ancillae in order to repetitively readout the state of the electronic spin. Using coherent manipulation of a single nitrogen vacancy center in room-temperature diamond, full quantum control of an electronic-nuclear system consisting of up to three spins was achieved. We took advantage of a single nuclear-spin memory in order to obtain a 10-fold enhancement in the signal amplitude of the electronic spin readout. We also present a two-level, concatenated procedure to improve the readout by use of a pair of nuclear spin ancillae, an important step toward the realization of robust quantum information processors using electronic- and nuclear-spin qubits. Our technique can be used to improve the sensitivity and speed of spin-based nanoscale diamond magnetometers.
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Affiliation(s)
- L Jiang
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
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14
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Maze JR, Stanwix PL, Hodges JS, Hong S, Taylor JM, Cappellaro P, Jiang L, Dutt MVG, Togan E, Zibrov AS, Yacoby A, Walsworth RL, Lukin MD. Nanoscale magnetic sensing with an individual electronic spin in diamond. Nature 2008; 455:644-7. [PMID: 18833275 DOI: 10.1038/nature07279] [Citation(s) in RCA: 549] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Accepted: 07/18/2008] [Indexed: 11/09/2022]
Abstract
Detection of weak magnetic fields with nanoscale spatial resolution is an outstanding problem in the biological and physical sciences. For example, at a distance of 10 nm, the spin of a single electron produces a magnetic field of about 1 muT, and the corresponding field from a single proton is a few nanoteslas. A sensor able to detect such magnetic fields with nanometre spatial resolution would enable powerful applications, ranging from the detection of magnetic resonance signals from individual electron or nuclear spins in complex biological molecules to readout of classical or quantum bits of information encoded in an electron or nuclear spin memory. Here we experimentally demonstrate an approach to such nanoscale magnetic sensing, using coherent manipulation of an individual electronic spin qubit associated with a nitrogen-vacancy impurity in diamond at room temperature. Using an ultra-pure diamond sample, we achieve detection of 3 nT magnetic fields at kilohertz frequencies after 100 s of averaging. In addition, we demonstrate a sensitivity of 0.5 muT Hz(-1/2) for a diamond nanocrystal with a diameter of 30 nm.
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Affiliation(s)
- J R Maze
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
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15
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Tsai LL, Mair RW, Rosen MS, Patz S, Walsworth RL. An open-access, very-low-field MRI system for posture-dependent 3He human lung imaging. J Magn Reson 2008; 193:274-85. [PMID: 18550402 PMCID: PMC2572034 DOI: 10.1016/j.jmr.2008.05.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Revised: 05/14/2008] [Accepted: 05/14/2008] [Indexed: 05/20/2023]
Abstract
We describe the design and operation of an open-access, very-low-field, magnetic resonance imaging (MRI) system for in vivo hyperpolarized 3He imaging of the human lungs. This system permits the study of lung function in both horizontal and upright postures, a capability with important implications in pulmonary physiology and clinical medicine, including asthma and obesity. The imager uses a bi-planar B(0) coil design that produces an optimized 65 G (6.5 mT) magnetic field for 3He MRI at 210 kHz. Three sets of bi-planar coils produce the x, y, and z magnetic field gradients while providing a 79-cm inter-coil gap for the imaging subject. We use solenoidal Q-spoiled RF coils for operation at low frequencies, and are able to exploit insignificant sample loading to allow for pre-tuning/matching schemes and for accurate pre-calibration of flip angles. We obtain sufficient SNR to acquire 2D 3He images with up to 2.8mm resolution, and present initial 2D and 3D 3He images of human lungs in both supine and upright orientations. 1H MRI can also be performed for diagnostic and calibration reasons.
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Affiliation(s)
- L. L. Tsai
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139
- Harvard Medical School, Boston, MA 02115
| | - R. W. Mair
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138
| | - M. S. Rosen
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138
- Department of Physics, Harvard University, Cambridge, MA 02138
| | - S. Patz
- Harvard Medical School, Boston, MA 02115
- Department of Radiology, Brigham and Women’s Hospital, Boston, MA 02115
| | - R. L. Walsworth
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138
- Department of Physics, Harvard University, Cambridge, MA 02138
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16
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Klein M, Tsai LL, Rosen MS, Pavlin T, Candela D, Walsworth RL. Interstitial gas and density segregation of vertically vibrated granular media. Phys Rev E Stat Nonlin Soft Matter Phys 2006; 74:010301. [PMID: 16907043 DOI: 10.1103/physreve.74.010301] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2005] [Indexed: 05/11/2023]
Abstract
We report experimental studies of the effect of interstitial gas on mass-density segregation in a vertically vibrated mixture of equal-sized bronze and glass spheres. Sufficiently strong vibration in the presence of interstitial gas induces vertical segregation into sharply separated bronze and glass layers. We find that the segregated steady state (i.e., bronze or glass layer on top) is a sensitive function of gas pressure and viscosity, as well as vibration frequency and amplitude. In particular, we identify distinct regimes of behavior that characterize the change from bronze-on-top to glass-on-top steady state.
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Affiliation(s)
- M Klein
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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17
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Ruset IC, Tsai LL, Mair RW, Patz S, Hrovat MI, Rosen MS, Muradian I, Ng J, Topulos GP, Butler JP, Walsworth RL, Hersman FW. A System for Open-Access He Human Lung Imaging at Very Low Field. Concepts Magn Reson Part B Magn Reson Eng 2006; 29:210-221. [PMID: 20354575 PMCID: PMC2846659 DOI: 10.1002/cmr.b.20075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We describe a prototype system built to allow open-access very-low-field MRI of human lungs using laser-polarized (3)He gas. The system employs an open four-coil electromagnet with an operational B(0) field of 4 mT, and planar gradient coils that generate gradient fields up to 0.18 G/cm in the x and y direction and 0.41 G/cm in the z direction. This system was used to obtain (1)H and (3)He phantom images and supine and upright (3)He images of human lungs. We include discussion on challenges unique to imaging at 50 -200 kHz, including noise filtering and compensation for narrow-bandwidth coils.
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Affiliation(s)
- I C Ruset
- Department of Physics, University of New Hampshire, Physics Department, 9 Library Way, DeMeritt Hall, Durham, New Hampshire 03824
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18
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Mair RW, Hrovat MI, Patz S, Rosen MS, Ruset IC, Topulos GP, Tsai LL, Butler JP, Hersman FW, Walsworth RL. 3He lung imaging in an open access, very-low-field human magnetic resonance imaging system. Magn Reson Med 2005; 53:745-9. [PMID: 15799045 DOI: 10.1002/mrm.20456] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The human lung and its functions are extremely sensitive to gravity; however, the conventional high-field magnets used for most laser-polarized (3)He MRI of the human lung restrict subjects to lying horizontally. Imaging of human lungs using inhaled laser-polarized (3)He gas is demonstrated in an open-access very-low-magnetic-field (<5 mT) MRI instrument. This prototype device employs a simple, low-cost electromagnet, with an open geometry that allows variation of the orientation of the imaging subject in a two-dimensional plane. As a demonstration, two-dimensional lung images were acquired with 4-mm in-plane resolution from a subject in two orientations: lying supine and sitting in a vertical position with one arm raised. Experience with this prototype device will guide optimization of a second-generation very-low-field imager to enable studies of human pulmonary physiology as a function of subject orientation.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 59, Cambridge, Massachusetts 02138, USA.
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19
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Canè F, Bear D, Phillips DF, Rosen MS, Smallwood CL, Stoner RE, Walsworth RL, Kostelecký VA. Bound on Lorentz and CPT violating boost effects for the neutron. Phys Rev Lett 2004; 93:230801. [PMID: 15601138 DOI: 10.1103/physrevlett.93.230801] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2003] [Indexed: 05/14/2023]
Abstract
A search for an annual variation of a daily sidereal modulation of the frequency difference between colocated 129Xe and 3He Zeeman masers sets a stringent limit on boost-dependent Lorentz and CPT violation involving the neutron, consistent with no effect at the level of 150 nHz. In the framework of the general standard-model extension, the present result provides the first clean test for the fermion sector of the symmetry of spacetime under boost transformations at a level of 10(-27) GeV.
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Affiliation(s)
- F Canè
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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20
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Canè F, Bear D, Phillips DF, Rosen MS, Smallwood CL, Stoner RE, Walsworth RL, Kostelecký VA. Bound on Lorentz and CPT violating boost effects for the neutron. Phys Rev Lett 2004. [PMID: 15601138 DOI: 10.1103/phys-revlett.93.230801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
A search for an annual variation of a daily sidereal modulation of the frequency difference between colocated 129Xe and 3He Zeeman masers sets a stringent limit on boost-dependent Lorentz and CPT violation involving the neutron, consistent with no effect at the level of 150 nHz. In the framework of the general standard-model extension, the present result provides the first clean test for the fermion sector of the symmetry of spacetime under boost transformations at a level of 10(-27) GeV.
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Affiliation(s)
- F Canè
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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21
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Wang R, Mair RW, Rosen MS, Cory DG, Walsworth RL. Simultaneous measurement of rock permeability and effective porosity using laser-polarized noble gas NMR. Phys Rev E Stat Nonlin Soft Matter Phys 2004; 70:026312. [PMID: 15447593 DOI: 10.1103/physreve.70.026312] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Indexed: 05/24/2023]
Abstract
We report simultaneous measurements of the permeability and effective porosity of oil-reservoir rock cores using one-dimensional NMR imaging of the penetrating flow of laser-polarized xenon gas. The permeability result agrees well with industry standard techniques, whereas effective porosity is not easily determined by other methods. This NMR technique may have applications to the characterization of fluid flow in a wide variety of porous and granular media.
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Affiliation(s)
- R Wang
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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22
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Huan C, Yang X, Candela D, Mair RW, Walsworth RL. NMR experiments on a three-dimensional vibrofluidized granular medium. Phys Rev E Stat Nonlin Soft Matter Phys 2004; 69:041302. [PMID: 15169012 DOI: 10.1103/physreve.69.041302] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2003] [Revised: 10/16/2003] [Indexed: 05/24/2023]
Abstract
A three-dimensional granular system fluidized by vertical container vibrations was studied using pulsed field gradient NMR coupled with one-dimensional magnetic resonance imaging. The system consisted of mustard seeds vibrated vertically at 50 Hz, and the number of layers N(l)<or=4 was sufficiently low to achieve a nearly time-independent granular fluid. Using NMR, the vertical profiles of density and granular temperature were directly measured, along with the distributions of vertical and horizontal grain velocities. The velocity distributions showed modest deviations from Maxwell-Boltzmann statistics, except for the vertical velocity distribution near the sample bottom, which was highly skewed and non-Gaussian. Data taken for three values of N(l) and two dimensionless accelerations Gamma=15,18 were fitted to a hydrodynamic theory, which successfully models the density and temperature profiles away from the vibrating container bottom. A temperature inversion near the free upper surface is observed, in agreement with predictions based on the hydrodynamic parameter micro which is nonzero only in inelastic systems.
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Affiliation(s)
- Chao Huan
- Physics Department, University of Massachusetts, Amherst, Massachusetts 01003, USA
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23
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Abstract
We experimentally demonstrate emission of two quantum-mechanically correlated light pulses with a time delay that is coherently controlled via temporal storage of photonic states in an ensemble of rubidium atoms. The experiment is based on Raman scattering, which produces correlated pairs of spin-flipped atoms and photons, followed by coherent conversion of the atomic states into a different photon beam after a controllable delay. This resonant nonlinear optical process is a promising technique for potential applications in quantum communication.
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Affiliation(s)
- C H van der Wal
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
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24
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Mair RW, Wang R, Rosen MS, Candela D, Cory DG, Walsworth RL. Applications of controlled-flow laser-polarized xenon gas to porous and granular media study. Magn Reson Imaging 2003; 21:287-92. [PMID: 12850720 DOI: 10.1016/s0730-725x(03)00156-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We report initial NMR studies of continuous flow laser-polarized xenon gas, both in unrestricted tubing, and in a model porous media. The study uses Pulsed Gradient Spin Echo-based techniques in the gas-phase, with the aim of obtaining more sophisticated information than just translational self-diffusion coefficients. Pulsed Gradient Echo studies of continuous flow laser-polarized xenon gas in unrestricted tubing indicate clear diffraction minima resulting from a wide distribution of velocities in the flow field. The maximum velocity experienced in the flow can be calculated from this minimum, and is seen to agree with the information from the complete velocity spectrum, or motion propagator, as well as previously published images. The susceptibility of gas flows to parameters such as gas mixture content, and hence viscosity, are observed in experiments aimed at identifying clear structural features from echo attenuation plots of gas flow in porous media. Gas-phase NMR scattering, or position correlation flow-diffraction, previously clearly seen in the echo attenuation data from laser-polarized xenon flowing through a 2 mm glass bead pack is not so clear in experiments using a different gas mixture. A propagator analysis shows most gas in the sample remains close to static, while a small portion moves through a presumably near-unimpeded path at high velocities.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA.
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25
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Abstract
We report initial NMR studies of (i) xenon gas diffusion in model heterogeneous porous media and (ii) continuous flow laser-polarized xenon gas. Both areas utilize the pulsed gradient spin-echo (PGSE) techniques in the gas phase, with the aim of obtaining more sophisticated information than just translational self-diffusion coefficients--a brief overview of this area is provided in the Introduction. The heterogeneous or multiple-length scale model porous media consisted of random packs of mixed glass beads of two different sizes. We focus on observing the approach of the time-dependent gas diffusion coefficient, D(t) (an indicator of mean squared displacement), to the long-time asymptote, with the aim of understanding the long-length scale structural information that may be derived from a heterogeneous porous system. We find that D(t) of imbibed xenon gas at short diffusion times is similar for the mixed bead pack and a pack of the smaller sized beads alone, hence reflecting the pore surface area to volume ratio of the smaller bead sample. The approach of D(t) to the long-time limit follows that of a pack of the larger sized beads alone, although the limiting D(t) for the mixed bead pack is lower, reflecting the lower porosity of the sample compared to that of a pack of mono-sized glass beads. The Pade approximation is used to interpolate D(t) data between the short- and long-time limits. Initial studies of continuous flow laser-polarized xenon gas demonstrate velocity-sensitive imaging of much higher flows than can generally be obtained with liquids (20-200 mm s-1). Gas velocity imaging is, however, found to be limited to a resolution of about 1 mm s-1 owing to the high diffusivity of gases compared with liquids. We also present the first gas-phase NMR scattering, or diffusive-diffraction, data, namely flow-enhanced structural features in the echo attenuation data from laser-polarized xenon flowing through a 2 mm glass bead pack.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA.
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26
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Mair RW, Sen PN, Hürlimann MD, Patz S, Cory DG, Walsworth RL. The narrow pulse approximation and long length scale determination in xenon gas diffusion NMR studies of model porous media. J Magn Reson 2002; 156:202-212. [PMID: 12165255 DOI: 10.1006/jmre.2002.2540] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report a systematic study of xenon gas diffusion NMR in simple model porous media, random packs of mono-sized glass beads, and focus on three specific areas peculiar to gas-phase diffusion. These topics are: (i) diffusion of spins on the order of the pore dimensions during the application of the diffusion encoding gradient pulses in a PGSE experiment (breakdown of the narrow pulse approximation and imperfect background gradient cancellation), (ii) the ability to derive long length scale structural information, and (iii) effects of finite sample size. We find that the time-dependent diffusion coefficient, D(t), of the imbibed xenon gas at short diffusion times in small beads is significantly affected by the gas pressure. In particular, as expected, we find smaller deviations between measured D(t) and theoretical predictions as the gas pressure is increased, resulting from reduced diffusion during the application of the gradient pulse. The deviations are then completely removed when water D(t) is observed in the same samples. The use of gas also allows us to probe D(t) over a wide range of length scales and observe the long time asymptotic limit which is proportional to the inverse tortuosity of the sample, as well as the diffusion distance where this limit takes effect (approximately 1-1.5 bead diameters). The Padé approximation can be used as a reference for expected xenon D(t) data between the short and the long time limits, allowing us to explore deviations from the expected behavior at intermediate times as a result of finite sample size effects. Finally, the application of the Padé interpolation between the long and the short time asymptotic limits yields a fitted length scale (the Padé length), which is found to be approximately 0.13b for all bead packs, where b is the bead diameter.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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27
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Butler JP, Mair RW, Hoffmann D, Hrovat MI, Rogers RA, Topulos GP, Walsworth RL, Patz S. Measuring surface-area-to-volume ratios in soft porous materials using laser-polarized xenon interphase exchange nuclear magnetic resonance. J Phys Condens Matter 2002; 14:L297-304. [PMID: 12741395 PMCID: PMC2194751 DOI: 10.1088/0953-8984/14/13/103] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We demonstrate a minimally invasive nuclear magnetic resonance (NMR) technique that enables determination of the surface-area-to-volume ratio (S/V) of soft porous materials from measurements of the diffusive exchange of laser-polarized 129Xe between gas in the pore space and 129Xe dissolved in the solid phase. We apply this NMR technique to porous polymer samples and find approximate agreement with destructive stereological measurements of S/V obtained with optical confocal microscopy. Potential applications of laser-polarized xenon interphase exchange NMR include measurements of in vivo lung function in humans and characterization of gas chromatography columns.
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Affiliation(s)
- J P Butler
- Harvard School of Public Health, Boston, MA 02115, USA
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28
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Yang X, Huan C, Candela D, Mair RW, Walsworth RL. Measurements of grain motion in a dense, three-dimensional granular fluid. Phys Rev Lett 2002; 88:044301. [PMID: 11801123 DOI: 10.1103/physrevlett.88.044301] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2001] [Indexed: 05/23/2023]
Abstract
We have used an NMR technique to measure the short-time, three-dimensional displacement of grains in a system of mustard seeds vibrated vertically at 15 g. The technique averages over a time interval in which the grains move ballistically, giving a direct measurement of the granular temperature profile. The dense, lower portion of the sample is well described by a recent hydrodynamic theory for inelastic hard spheres. Near the free upper surface the mean free path is longer than the particle diameter and the hydrodynamic description fails.
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Affiliation(s)
- Xiaoyu Yang
- Physics Department, University of Massachusetts, Amherst, Massachusetts 01003, USA
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29
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Zhao L, Mulkern R, Tseng CH, Williamson D, Patz S, Kraft R, Walsworth RL, Jolesz FA, Albert MS. Gradient-echo imaging considerations for hyperpolarized 129Xe MR. J Magn Reson B 2001; 113:179-83. [PMID: 11543610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Affiliation(s)
- L Zhao
- Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115, USA
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30
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Abstract
Using a novel NMR scheme we observed persistence in 1D gas diffusion. Analytical approximations and numerical simulations have indicated that for an initially random array of spins undergoing diffusion, the probability p(t) that the average spin magnetization in a given region has not changed sign (i.e., "persists") up to time t follows a power law t(-straight theta), where straight theta depends on the dimensionality of the system. Using laser-polarized 129Xe gas, we prepared an initial "quasirandom" 1D array of spin magnetization and then monitored the ensemble's evolution due to diffusion using real-time NMR imaging. Our measurements are consistent with analytical and numerical predictions of straight theta approximately 0.12.
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Affiliation(s)
- G P Wong
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA
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31
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Mair RW, Hürlimann MD, Sen PN, Schwartz LM, Patz S, Walsworth RL. Tortuosity measurement and the effects of finite pulse widths on xenon gas diffusion NMR studies of porous media. Magn Reson Imaging 2001; 19:345-51. [PMID: 11445310 DOI: 10.1016/s0730-725x(01)00247-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We have extended the utility of NMR as a technique to probe porous media structure over length scales of approximately 100-2000 microm by using the spin 1/2 noble gas 129Xe imbibed into the system's pore space. Such length scales are much greater than can be probed with NMR diffusion studies of water-saturated porous media. We utilized Pulsed Gradient Spin Echo NMR measurements of the time-dependent diffusion coefficient, D(t), of the xenon gas filling the pore space to study further the measurements of both the pore surface-area-to-volume ratio, S/V(p), and the tortuosity (pore connectivity) of the medium. In uniform-size glass bead packs, we observed D(t) decreasing with increasing t, reaching an observed asymptote of approximately 0.62-0.65D(0), that could be measured over diffusion distances extending over multiple bead diameters. Measurements of D(t)/D(0) at differing gas pressures showed this tortuosity limit was not affected by changing the characteristic diffusion length of the spins during the diffusion encoding gradient pulse. This was not the case at the short time limit, where D(t)/D(0) was noticeably affected by the gas pressure in the sample. Increasing the gas pressure, and hence reducing D(0) and the diffusion during the gradient pulse served to reduce the previously observed deviation of D(t)/D(0) from the S/V(p) relation. The Pade approximation is used to interpolate between the long and short time limits in D(t). While the short time D(t) points lay above the interpolation line in the case of small beads, due to diffusion during the gradient pulse on the order of the pore size, it was also noted that the experimental D(t) data fell below the Pade line in the case of large beads, most likely due to finite size effects.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA.
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32
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Abstract
We report an experiment in which a light pulse is effectively decelerated and trapped in a vapor of Rb atoms, stored for a controlled period of time, and then released on demand. We accomplish this "storage of light" by dynamically reducing the group velocity of the light pulse to zero, so that the coherent excitation of the light is reversibly mapped into a Zeeman (spin) coherence of the Rb vapor.
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Affiliation(s)
- D F Phillips
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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33
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Bear D, Stoner RE, Walsworth RL, Kostelecky VA, Lane CD. Limit on lorentz and CPT violation of the neutron using a two-species noble-Gas maser. Phys Rev Lett 2000. [PMID: 11102181 DOI: 10.1103/physrevlett.89.209902] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A search for sidereal variations in the frequency difference between co-located 129Xe and 3He Zeeman masers sets the most stringent limit to date on leading-order Lorentz and CPT violation involving the neutron, consistent with no effect at the level of 10(-31) GeV.
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Affiliation(s)
- D Bear
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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34
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Bear D, Stoner RE, Walsworth RL, Kostelecky VA, Lane CD. Limit on lorentz and CPT violation of the neutron using a two-species noble-Gas maser. Phys Rev Lett 2000; 85:5038-5041. [PMID: 11102181 DOI: 10.1103/physrevlett.85.5038] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2000] [Indexed: 05/23/2023]
Abstract
A search for sidereal variations in the frequency difference between co-located 129Xe and 3He Zeeman masers sets the most stringent limit to date on leading-order Lorentz and CPT violation involving the neutron, consistent with no effect at the level of 10(-31) GeV.
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Affiliation(s)
- D Bear
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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35
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Abstract
The large diffusion coefficients of gases result in significant spin motion during the application of gradient pulses that typically last a few milliseconds in most NMR experiments. In restricted environments, such as the lung, this rapid gas diffusion can lead to violations of the narrow pulse approximation, a basic assumption of the standard Stejskal-Tanner NMR method of diffusion measurement. We therefore investigated the effect of a common, biologically inert buffer gas, sulfur hexafluoride (SF(6)), on (129)Xe NMR and diffusion. We found that the contribution of SF(6) to (129)Xe T(1) relaxation in a 1:1 xenon/oxygen mixture is negligible up to 2 bar of SF(6) at standard temperature. We also measured the contribution of SF(6) gas to (129)Xe T(2) relaxation, and found it to scale inversely with pressure, with this contribution approximately equal to 1 s for 1 bar SF(6) pressure and standard temperature. Finally, we found the coefficient of (129)Xe diffusion through SF(6) to be approximately 4.6 x 10(-6) m(2)s(-1) for 1 bar pressure of SF(6) and standard temperature, which is only 1.2 times smaller than the (129)Xe self diffusion coefficient for 1 bar (129)Xe pressure and standard temperature. From these measurements we conclude that SF(6) will not sufficiently reduce (129)Xe diffusion to allow accurate surface-area/volume ratio measurements in human alveoli using time-dependent gas diffusion NMR.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 59, Cambridge, MA 02138, USA.
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36
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Mair RW, Tseng CH, Wong GP, Cory DG, Walsworth RL. Magnetic resonance imaging of convection in laser-polarized xenon. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 2000; 61:2741-2748. [PMID: 11046596 DOI: 10.1103/physreve.61.2741] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/1999] [Indexed: 05/23/2023]
Abstract
We demonstrate nuclear magnetic resonance (NMR) imaging of the flow and diffusion of laser-polarized xenon (129Xe) gas undergoing convection above evaporating laser-polarized liquid xenon. The large xenon NMR signal provided by the laser-polarization technique allows more rapid imaging than one can achieve with thermally polarized gas-liquid systems, permitting shorter time-scale events such as rapid gas flow and gas-liquid dynamics to be observed. Two-dimensional velocity-encoded imaging shows convective gas flow above the evaporating liquid xenon, and also permits the measurement of enhanced gas diffusion near regions of large velocity variation.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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37
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Wong GP, Tseng CH, Pomeroy VR, Mair RW, Hinton DP, Hoffmann D, Stoner RE, Hersman FW, Cory DG, Walsworth RL. A system for low field imaging of laser-polarized noble gas. J Magn Reson 1999; 141:217-27. [PMID: 10579945 DOI: 10.1006/jmre.1999.1904] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We describe a device for performing MRI with laser-polarized noble gas at low magnetic fields (<50 G). The system is robust, portable, inexpensive, and provides gas-phase imaging resolution comparable to that of high field clinical instruments. At 20.6 G, we have imaged laser-polarized (3)He (Larmor frequency of 67 kHz) in both sealed glass cells and excised rat lungs, using approximately 0.1 G/cm gradients to achieve approximately 1 mm(2) resolution. In addition, we measured (3)He T(2)(*) times greater than 100 ms in excised rat lungs, which is roughly 20 times longer than typical values observed at high ( approximately 2 T) fields. We include a discussion of the practical considerations for working at low magnetic fields and conclude with evidence of radiation damping in this system.
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Affiliation(s)
- G P Wong
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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38
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Abstract
We show that gas diffusion nuclear magnetic resonance (GD-NMR) provides a powerful technique for probing the structure of porous media. In random packs of glass beads, using both laser-polarized and thermally polarized xenon gas, we find that GD-NMR can accurately measure the pore space surface-area-to-volume ratio, S/V rho, and the tortuosity, alpha (the latter quantity being directly related to the system's transport properties). We also show that GD-NMR provides a good measure of the tortuosity of sandstone and complex carbonate rocks.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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39
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Abstract
A single-shot pulsed gradient stimulated echo sequence is introduced to address the challenges of diffusion measurements of laser polarized 3He and 129Xe gas. Laser polarization enhances the NMR sensitivity of these noble gases by >10(3), but creates an unstable, nonthermal polarization that is not readily renewable. A new method is presented which permits parallel acquisition of the several measurements required to determine a diffusive attenuation curve. The NMR characterization of a sample's diffusion behavior can be accomplished in a single measurement, using only a single polarization step. As a demonstration, the diffusion coefficient of a sample of laser-polarized 129Xe gas is measured via this method.
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Affiliation(s)
- S Peled
- Department of Nuclear Engineering, Massachusetts Institute of Technology, 150 Albany Street, Cambridge, Massachusetts 02139, USA
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40
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Abstract
Pulsed-field-gradient NMR techniques are demonstrated for measurements of time-dependent gas diffusion. The standard PGSE technique and variants, applied to a free gas mixture of thermally polarized xenon and O2, are found to provide a reproducible measure of the xenon diffusion coefficient (5.71 x 10(-6) m2 s-1 for 1 atm of pure xenon), in excellent agreement with previous, non-NMR measurements. The utility of pulsed-field-gradient NMR techniques is demonstrated by the first measurement of time-dependent (i.e., restricted) gas diffusion inside a porous medium (a random pack of glass beads), with results that agree well with theory. Two modified NMR pulse sequences derived from the PGSE technique (named the Pulsed Gradient Echo, or PGE, and the Pulsed Gradient Multiple Spin Echo, or PGMSE) are also applied to measurements of time dependent diffusion of laser polarized xenon gas, with results in good agreement with previous measurements on thermally polarized gas. The PGMSE technique is found to be superior to the PGE method, and to standard PGSE techniques and variants, for efficiently measuring laser polarized noble gas diffusion over a wide range of diffusion times.
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Affiliation(s)
- R W Mair
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, 02138, USA
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41
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Tseng CH, Wong GP, Pomeroy VR, Mair RW, Hinton DP, Hoffmann D, Stoner RE, Hersman FW, Cory DG, Walsworth RL. Low-field MRI of laser polarized noble gas. Phys Rev Lett 1998; 81:3785-3788. [PMID: 11543589 DOI: 10.1103/physrevlett.81.3785] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
NMR images of laser polarized 3He gas were obtained at 21 G using a simple, homebuilt instrument. At such low fields magnetic resonance imaging (MRI) of thermally polarized samples (e.g., water) is not practical. Low-field noble gas MRI has novel scientific, engineering, and medical applications. Examples include portable systems for diagnosis of lung disease, as well as imaging of voids in porous media and within metallic systems.
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Affiliation(s)
- C H Tseng
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA
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42
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Abstract
Laser-polarized 129Xe dissolved in a foam preparation of fresh human blood was investigated. The NMR signal of 129Xe dissolved in blood was enhanced by creating a foam in which the dissolved 129Xe exchanged with a large reservoir of gaseous laser-polarized 129Xe. The dissolved 129Xe T1 in this system was found to be significantly shorter in oxygenated blood than in deoxygenated blood. The T1 of 129Xe dissolved in oxygenated blood foam was found to be approximately 21 (+/-5) s, and in deoxygenated blood foam to be greater than 40 s. To understand the oxygenation trend, T1 measurements were also made on plasma and hemoglobin foam preparations. The measurement technique using a foam gas-liquid exchange interface may also be useful for studying foam coarsening and other liquid physical properties.
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Affiliation(s)
- C H Tseng
- Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
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Stoner RE, Rosenberry MA, Wright JT, Chupp TE, Oteiza ER, Walsworth RL. Demonstration of a Two Species Noble Gas Maser. Phys Rev Lett 1996; 77:3971-3974. [PMID: 10062355 DOI: 10.1103/physrevlett.77.3971] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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44
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Abstract
Magnetic resonance imaging using laser-polarized 129Xe is a new technique first demonstrated by Albert et. al. (Nature 370, 1994) who obtained a 129Xe image of an excised mouse lung. This paper describes the factors influencing the accumulation of inhaled, polarized 129Xe in human tissue. The resulting model predicts the 129Xe magnetization in different tissues as a function of the time from the start of inhalation, the tissue perfusion rate and partition coefficient for xenon, and the relevant T1 decay times. The relaxation times of 129Xe in biological tissues are not yet known precisely. Substitution of estimated values for these parameters results in an expected signal-to-noise ratio (SNR) from polarized 129Xe MR in the brain of approximately 2% of the equivalent SNR from proton MR.
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Affiliation(s)
- S Peled
- M.I.T., Division of Health Sciences and Technology, Boston, Massachusetts
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Sakai K, Bilek AM, Oteiza E, Walsworth RL, Balamore D, Jolesz FA, Albert MS. Temporal dynamics of hyperpolarized 129Xe resonances in living rats. J Magn Reson B 1996; 111:300-4. [PMID: 8661297 DOI: 10.1006/jmrb.1996.0098] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- K Sakai
- Department of Radiology, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
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46
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Albert MS, Tseng CH, Williamson D, Oteiza ER, Walsworth RL, Kraft B, Kacher D, Holman BL, Jolesz FA. Hyperpolarized 129Xe MR imaging of the oral cavity. J Magn Reson B 1996; 111:204-7. [PMID: 8661283 DOI: 10.1006/jmrb.1996.0084] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- M S Albert
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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48
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Walsworth RL, Silvera IF, Mattison EM, Vessot RF. Measurement of a hyperfine-induced spin-exchange frequency shift in atomic hydrogen. Phys Rev A 1992; 46:2495-2512. [PMID: 9908407 DOI: 10.1103/physreva.46.2495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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49
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Walsworth RL, Silvera IF. Nonlinear quantum mechanics for systems of composite spin. Phys Rev A 1990; 42:63-68. [PMID: 9903777 DOI: 10.1103/physreva.42.63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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50
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Walsworth RL, Silvera IF, Mattison EM, Vessot RF. Test of the linearity of quantum mechanics in an atomic system with a hydrogen maser. Phys Rev Lett 1990; 64:2599-2602. [PMID: 10041761 DOI: 10.1103/physrevlett.64.2599] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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