High frequency dynamic nuclear polarization: New directions for the 21st century

Griffin, Robert G.; Swager, Timothy M.; Temkin, Richard J.

doi:10.1016/j.jmr.2019.07.019

Cited by 42 publications

(63 citation statements)

References 83 publications

(82 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These hardwarebased methods typically use a lock signal from a reference sample or nucleus (e.g., deuterium), and either the field or the NMR transmitter frequency is adjusted accordingly (Baker and Burd, 1957;Maly et al, 2006;Markiewicz, 2002;Paulson and Zilm, 2005). In contrast, software-based methods can be also used to account for magnetic field drifts (Ha et al, 2014;Najbauer and Andreas, 2019). Using a software-based method to correct for the field drift has the advantage that no additional hardware is required.…”

Section: Interleaved Spectral Referencing For Magnetic Field Drift Correctionmentioning

confidence: 99%

“…We used a compact, single-channel NMR spectrometer with no lock channel. This type of hardware is commonly found in NMR applications for process monitoring or well-logging applications, which often have strict space restrictions, and adding additional hardware is challenging or simply not possible (Ha et al, 2014;Mandal et al, 2014;Song and Kausik, 2019).…”

Section: Interleaved Spectral Referencing For Magnetic Field Drift Correctionmentioning

confidence: 99%

See 1 more Smart Citation

Overhauser dynamic nuclear polarization (ODNP)-enhanced two-dimensional proton NMR spectroscopy at low magnetic fields

Keller

Maly

2021

Magn. Reson.

View full text Add to dashboard Cite

Abstract. The majority of low-field Overhauser dynamic nuclear polarization (ODNP) experiments reported so far have been 1D NMR experiments to study molecular dynamics and in particular hydration dynamics. In this work, we demonstrate the application of ODNP-enhanced 2D J-resolved (JRES) spectroscopy to improve spectral resolution beyond the limit imposed by the line broadening introduced by the paramagnetic polarizing agent. Using this approach, we are able to separate the overlapping multiplets of ethyl crotonate into a second dimension and clearly identify each chemical site individually. Crucial to these experiments is interleaved spectral referencing, a method introduced to compensate for temperature-induced field drifts over the course of the NMR acquisition. This method does not require additional hardware such as a field-frequency lock, which is especially challenging when designing compact systems.

show abstract

Section: Interleaved Spectral Referencing For Magnetic Field Drift Correctionmentioning

confidence: 99%

Section: Interleaved Spectral Referencing For Magnetic Field Drift Correctionmentioning

confidence: 99%

Overhauser dynamic nuclear polarization (ODNP)-enhanced two-dimensional proton NMR spectroscopy at low magnetic fields

Keller

Maly

2021

Magn. Reson.

View full text Add to dashboard Cite

show abstract

“…In state-of-the-art DNP-NMR experiments, high power CW sources, namely gyrotrons [25], [4], are used. Gyrotrons are oscillators and therefore they provide the high power CW signals without the requirement of an external input source.…”

Section: Backward Wave Oscillatormentioning

confidence: 99%

“…I N a joint project of the Russian Science Foundation (RSF) and the Deutsche Forschungsgemeinschaft (DFG), led by the Institute of Applied Physics (IAP-RAS) in Nizhny Novgorod, Russia, and supported by the Institute for Pulsed Power and Microwave Technology (IHM-KIT), the generation of a periodic sequence of coherent, powerful, ultra-short RF pulses is studied [1]. Such powerful pulses of millimeter and sub-millimeter waves can be useful for a number of fundamental problems and practical applications, including novel pulsed Dynamic Nuclear Polarization (DNP)-Nuclear Magnetic Resonance (NMR) spectroscopy, diagnostics of plasmas, photochemistry and biophysics [2], [3], [4].…”

Section: Introductionmentioning

confidence: 99%

Extended Feedback System for Coupled Sub-THz Gyro-Devices to Provide New Regimes of Operation

Marek

Avramidis

Illy

et al. 2020

IEEE Trans. Electron Devices

View full text Add to dashboard Cite

A new type of high-power pulsed source in the millimeter and sub-millimeter frequency range, utilizing the method of passive mode locking, was proposed in 2015 by the Institute of Applied Physics (IAP-RAS) in Nizhny Novgorod. This principle, well known from laser physics, allows the generation of a periodic series of powerful, coherent, ultra-short pulses. In the millimeter and sub-millimeter wavelength range this can be realized using an amplifier and a saturable absorber coupled in a feedback loop. For the coupling of the two devices, a sophisticated feedback system is required. Such a system, based on simple overmoded waveguide components, was previously proposed by the authors. The present article shows how the proposed feedback system can be extended, allowing for a wide range of possible operation regimes for two coupled gyro-devices. Particularly noteworthy is the application of the modified feedback system for the realization of a two-stage amplifier in the sub-THz range. Furthermore, it seems to be possible to use two helical gyrodevices coupled in the proposed way as a source of coherent pulses, as a free-running or locked CW source, and as a twostage amplifier. In all cases, no design changes of the feedback system are required. Index Terms-sub-THz, high power, ultra-short pulses, passive mode locking, feedback system, quasi-optical.

show abstract

“…This trend can largely be seen as a response to fundamental, well-known traits of nuclear magnetic resonance (NMR), outstanding in its versatility and range of applications but inherently limited in its detection sensitivity. Understandably, much of the effort has been devoted to developing dynamic polarization strategies applicable to high magnetic fields, a route that promises to reap the benefits of enhanced NMR signals without sacrificing on spectral resolution [8][9][10]. On the other hand, low-field setups -especially those based on optical pumping and detection -allow the experimenter to study regimes otherwise difficult to access [11,12].…”

Section: Introductionmentioning

confidence: 99%

Nuclear spin temperature reversal via continuous radio-frequency driving

et al. 2021

View full text Add to dashboard Cite

Optical spin pumping of color centers in diamond is presently attracting broad interest as a platform for dynamic nuclear polarization at room temperature, but the mechanisms involved in the generation and transport of polarization within the host crystal are still partly understood. Here we investigate the impact of continuous radio-frequency (RF) excitation on the generation of nuclear magnetization produced by optical illumination. In the presence of RF excitation far removed from the nuclear Larmor frequency, we witness a magnetic-field-dependent sign reversal of the measured nuclear spin signal when the drive is sufficiently strong, a counterintuitive finding that immediately points to nontrivial spin dynamics. With the help of analytical and numerical modeling, we show our observations indicate a modified form of solid effect, down-converted from the microwave to the radio-frequency range through the driving of hybrid transitions involving one (or more) nuclei and two (or more) electron spins. Our results open intriguing opportunities for the manipulation of many-electron spin systems by exploiting hyperfine couplings as a means to access otherwise forbidden intraband transitions.

show abstract

High frequency dynamic nuclear polarization: New directions for the 21st century

Cited by 42 publications

References 83 publications

Overhauser dynamic nuclear polarization (ODNP)-enhanced two-dimensional proton NMR spectroscopy at low magnetic fields

Overhauser dynamic nuclear polarization (ODNP)-enhanced two-dimensional proton NMR spectroscopy at low magnetic fields

Extended Feedback System for Coupled Sub-THz Gyro-Devices to Provide New Regimes of Operation

Nuclear spin temperature reversal via continuous radio-frequency driving

Contact Info

Product

Resources

About