A presentation of pulsed nuclear magnetic resonance with full quantization of the radio frequency magnetic field

2002 ◽  
Vol 116 (18) ◽  
pp. 8036-8047 ◽  
Author(s):  
J. Jeener ◽  
F. Henin
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Radio Frequency ◽  
Frequency Magnetic Field ◽  
Pulsed Nuclear Magnetic Resonance ◽  
Nuclear Magnetic

scholarly journals FREQUENCY NOISE INFLUENCE ON FUNCTIONING OF FREDKIN QUANTUM GATE

2010 ◽  
pp. 118-126
Author(s):  
Gennadiy P. Gorskyi ◽  
Vitaliy G. Deibuk
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Standard Deviation ◽  
Magnetic Resonance ◽  
Radio Frequency ◽  
Correct Answer ◽  
Quantum Gate ◽  
Frequency Noise ◽  
Fredkin Gate ◽  
Frequency Magnetic Field

The influence of detuning of radio frequency magnetic field (RFMF) on the functioning of nuclear magnetic resonance (NMR) quantum Fredkin gate is considered in this paper. It is shown that detuning of frequency decreases a probability of correct answer. If the spectral broadband of RFMF signal is increasing, then the main value of correct answer probability is decreasing too and standard deviation of this probability is increasing.

scholarly journals Homogenous nuclear magnetic resonance probe using the space harmonics suppression method

2020 ◽  
Vol 9 (1) ◽  
pp. 117-125
Author(s):  
Pauline de Pellegars ◽  
Liu Pan ◽  
Rahima Sidi-Boulenouar ◽  
Eric Nativel ◽  
Michel Zanca ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Radio Frequency ◽  
Signal To Noise ◽  
Space Harmonics ◽  
Saddle Coil ◽  
Radio Frequency Coils ◽  
Shs Method ◽  
Nuclear Magnetic

Abstract. Nuclear magnetic resonance imaging (MRI) has became an unavoidable medical tool in spite of its poor sensitivity. This fact motivates the efforts to enhance the nuclear magnetic resonance (NMR) probe performance. Thus, the nuclear spin excitation and detection, classically performed using radio-frequency coils, are required to be highly sensitive and homogeneous. The space harmonics suppression (SHS) method, already demonstrated to construct coil producing homogenous static magnetic field, is used in this work to design radio-frequency coils. The SHS method is used to determine the distribution of the electrical conductive wires which are organized in a saddle-coil-like configuration. The theoretical study of these SHS coils allows one to expect an enhancement of the signal-to-noise ratio with respect to saddle coil. Coils prototypes were constructed and tested to measure 1H NMR signal at a low magnetic field (8 mT) and perform MRI acquired at a high magnetic field (3 T). The signal-to-noise ratios of these SHS coils are compared to the one of saddle coil and birdcage (in the 3 T case) of the same size under the same pulse sequence conditions demonstrating the performance enhancement allowed by the SHS coils.

Spin supercurrents and two-domain precession of magnetization in 3He-B

1987 ◽  
Vol 65 (11) ◽  
pp. 1510-1513
Author(s):  
I. A. Fomin
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nonuniform Magnetic Field ◽  
Small Oscillations ◽  
Induction Signal ◽  
Pulsed Nuclear Magnetic Resonance ◽  
Nuclear Magnetic

This is a brief review of recent investigations, both experimental and theoretical, of the phenomena observed in pulsed nuclear magnetic resonance experiments with superfluid 3He-B caused by spin supercurrents flowing in this liquid. Precession of magnetization in 3He-B in a nonuniform magnetic field results in the formation of a two-domain precessing structure, which accounts for the existence and properties of a long-lived induction signal observed in 3He-B. The relaxation of this structure and its small oscillations are discussed in connection with the experiments of Borovik-Romanov et al.

Nuclear magnetic resonance microscopy

1989 ◽  
Vol 47 ◽  
pp. 828-829
Author(s):  
Paul C. Lauterbur
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Fields ◽  
Signal To Noise ◽  
Field Gradients ◽  
Useful Signal ◽  
Magnetic Field Gradients ◽  
Observation Times ◽  
Nuclear Magnetic

Nuclear magnetic resonance imaging can reach microscopic resolution, as was noted many years ago, but the first serious attempt to explore the limits of the possibilities was made by Hedges. Resolution is ultimately limited under most circumstances by the signal-to-noise ratio, which is greater for small radio receiver coils, high magnetic fields and long observation times. The strongest signals in biological applications are obtained from water protons; for the usual magnetic fields used in NMR experiments (2-14 tesla), receiver coils of one to several millimeters in diameter, and observation times of a number of minutes, the volume resolution will be limited to a few hundred or thousand cubic micrometers. The proportions of voxels may be freely chosen within wide limits by varying the details of the imaging procedure. For isotropic resolution, therefore, objects of the order of (10μm) may be distinguished.Because the spatial coordinates are encoded by magnetic field gradients, the NMR resonance frequency differences, which determine the potential spatial resolution, may be made very large. As noted above, however, the corresponding volumes may become too small to give useful signal-to-noise ratios. In the presence of magnetic field gradients there will also be a loss of signal strength and resolution because molecular diffusion causes the coherence of the NMR signal to decay more rapidly than it otherwise would. This phenomenon is especially important in microscopic imaging.

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