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Related papers: Broadband Relaxation-Optimized Polarization Transf…

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Taking inspiration from NMR spectroscopy, periodic irradiation schemes have recently shown remarkable performance when implemented into pulsed dynamic nuclear polarization (DNP) sequences. This has prompted considerable interest in…

Relaxation effects impose fundamental limitations on our ability to coherently control quantum mechanical phenomena. In this letter, we establish physical limits on how closely can a quantum mechanical system be steered to a desired target…

Quantum Physics · Physics 2009-11-10 N. Khaneja , B. Luy , S. J. Glaser

Broadband inversion pulses that rotate all magnetization components 180 degrees about a given fixed axis are necessary for refocusing and mixing in high-resolution NMR spectroscopy. The relative merits of various methodologies for…

A wide variety of nuclear magnetic resonance experiments rely on the prediction and analysis of relaxation processes. Recently, innovative approaches have been introduced where the sample travels through a broad range of magnetic fields in…

The efficiency of dipole-dipole coupling driven coherence transfer experiments in solid-state NMR spectroscopy of powder samples is limited by dispersion of the orientation of the internuclear vectors relative to the external magnetic…

Quantum Physics · Physics 2009-11-13 N. Khaneja , C. Kehlet , S. J. Glaser , N. C. Nielsen

Experiments in coherent spectroscopy correspond to control of quantum mechanical ensembles guiding them from initial to final target states. The control inputs (pulse sequences) that accomplish these transformations should be designed to…

Quantum Physics · Physics 2009-11-07 Navin Khaneja , Timo Reiss , Burkhard Luy , Steffen J. Glaser

This paper proposes an effective diffusion equation method to analyze nuclear magnetic resonance (NMR) relaxation. NMR relaxation is a spin system recovery process, where the evolution of the spin system is affected by the random field due…

Chemical Physics · Physics 2021-03-31 Guoxing Lin

The past decade has demonstrated increasing interests in using optimal control based methods within coherent quantum controllable systems. The versatility of such methods has been demonstrated with particular elegance within nuclear…

Quantum Physics · Physics 2015-05-18 Ivan I. Maximov , Niels Chr. Nielsen , Julien Salomon , Gabriel Turinici

We consider the NMR signal from a permeable medium with a heterogeneous Larmor frequency component that varies on a scale comparable to the spin-carrier diffusion length. We focus on the mesoscopic part of the transverse relaxation, that…

Mesoscale and Nanoscale Physics · Physics 2008-10-23 D. S. Novikov , V. G. Kiselev

Hyperpolarization of nuclear spins enhances nuclear magnetic resonance signals, which play a key role for imaging and spectroscopy in the natural and life sciences. This signal amplification unlocks previously inaccessible techniques, such…

Polarization transfers are crucial building blocks in magnetic resonance experiments, i.e., they can be used to polarize insensitive nuclei and correlate nuclear spins in multidimensional NMR spectroscopy. The polarization can be…

Chemical Physics · Physics 2022-08-24 Zhenfeng Pang , Sheetal Jain , Chen Yang , Xueqian Kong , Kong Ooi Tan

We describe a new approach to precision NMR with hyperpolarized gases designed to mitigate NMR frequency shifts due to the alkali spin exchange field. The electronic spin polarization of optically pumped alkali atoms is square-wave…

Atomic Physics · Physics 2015-12-23 Anna Korver , Daniel Thrasher , Mike Bulatowicz , Thad Walker

In this manuscript, we present relaxation optimized methods for transfer of bilinear spin correlations along Ising spin chains. These relaxation optimized methods can be used as a building block for transfer of polarization between distant…

Quantum Physics · Physics 2014-01-17 Dionisis Stefanatos , Steffen J. Glaser , Navin Khaneja

Spin engineering of advanced pulse sequences has had a transformative impact on the development of nuclear magnetic resonance (NMR) spectroscopy, to an extending degree also electron paramagnetic resonance (EPR), and the hybrid between the…

Chemical Physics · Physics 2025-01-31 Jose P. Carvalho , Anders Bodholt Nielsen , Eniko Baligacs , Nino Wili , Niels Chr. Nielsen

Transverse NMR relaxation from spins diffusing through a random magnetic medium is sensitive to its structure on a mesoscopic scale. In particular, this results in the time-dependent relaxation rate. We show analytically and numerically…

Soft Condensed Matter · Physics 2018-10-12 Alexander Ruh , Philipp Emerich , Harald Scherer , Dmitry S. Novikov , Valerij G. Kiselev

The hyperpolarisation of nuclear spins within target molecules is a critical and complex challenge in magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) spectroscopy. Hyperpolarisation offers enormous gains in signal and…

Existing optimal control protocols for mitigating the effects of relaxation and/or RF inhomogeneity on broadband pulse performance are extended to the more difficult problem of designing robust, refocused, frequency selective excitation…

Instrumentation and Detectors · Physics 2015-06-03 Thomas E. Skinner , Naum I. Gershenzon , Manoj Nimbalkar , Steffen J. Glaser

The use of nuclear spins as physical sensing systems is disadvantaged by their low signal responsivity, particularly when compared to sensing techniques based on electron spins. This primarily results from the small nuclear gyromagnetic…

Dynamic nuclear polarisation (DNP) refers to a class of techniques used to increase the signal in nuclear magnetic resonance measurements by transferring spin polarisation from ensembles of highly polarised electrons to target nuclear…

Quantum Physics · Physics 2020-12-24 L. T. Hall , D. A. Broadway , A. Stacey , D. A. Simpson , J-P. Tetienne , L. C. L. Hollenberg

Solid state defects such as nitrogen vacancy (NV) centers in diamond have been utilized for NMR sensing at ambient temperatures for samples at the nano-scale and up to the micro-scale. Similar to standard NMR, NV-sensitivities can be…

Quantum Physics · Physics 2026-01-28 Oliver T. Whaites , Jaime García Oliván , Jorge Casanova
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