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Title: Spin Transfer from an Optically Pumped Alkali Vapor to a Solid

Abstract

We report enhancement of the spin polarization of {sup 133}Cs nuclei in CsH salt by spin transfer from an optically pumped cesium vapor. The nuclear polarization was 4.0 times the equilibrium polarization at 9.4 T and 137 deg. C, with larger enhancements at lower fields. This work is the first demonstration of spin transfer from a polarized alkali vapor to the nuclei of a solid, opening up new possibilities for research in hyperpolarized materials.

Authors:
; ; ;  [1]
  1. Joseph Henry Laboratory, Department of Physics, Princeton University, Princeton, New Jersey 08544 (United States)
Publication Date:
OSTI Identifier:
20951340
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 18; Other Information: DOI: 10.1103/PhysRevLett.98.183004; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; CESIUM 133; EQUILIBRIUM; POLARIZATION; SPIN; SPIN ORIENTATION; VAPORS

Citation Formats

Ishikawa, K., Patton, B., Jau, Y.-Y., and Happer, W. Spin Transfer from an Optically Pumped Alkali Vapor to a Solid. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.183004.
Ishikawa, K., Patton, B., Jau, Y.-Y., & Happer, W. Spin Transfer from an Optically Pumped Alkali Vapor to a Solid. United States. doi:10.1103/PHYSREVLETT.98.183004.
Ishikawa, K., Patton, B., Jau, Y.-Y., and Happer, W. Fri . "Spin Transfer from an Optically Pumped Alkali Vapor to a Solid". United States. doi:10.1103/PHYSREVLETT.98.183004.
@article{osti_20951340,
title = {Spin Transfer from an Optically Pumped Alkali Vapor to a Solid},
author = {Ishikawa, K. and Patton, B. and Jau, Y.-Y. and Happer, W.},
abstractNote = {We report enhancement of the spin polarization of {sup 133}Cs nuclei in CsH salt by spin transfer from an optically pumped cesium vapor. The nuclear polarization was 4.0 times the equilibrium polarization at 9.4 T and 137 deg. C, with larger enhancements at lower fields. This work is the first demonstration of spin transfer from a polarized alkali vapor to the nuclei of a solid, opening up new possibilities for research in hyperpolarized materials.},
doi = {10.1103/PHYSREVLETT.98.183004},
journal = {Physical Review Letters},
number = 18,
volume = 98,
place = {United States},
year = {Fri May 04 00:00:00 EDT 2007},
month = {Fri May 04 00:00:00 EDT 2007}
}
  • Calculations are presented of the limitations imposed by radiation trapping on the electron spin polarization produced in an alkali-metal vapor by optical pumping in a large magnetic field. It is found that electron spin polarizations of 90% are possible with Na densities up to 10 Z atoms/mT and ground-level relaxation times of 150 s in a large magnetic field using a cylindrical geometry of radius 7.5 x 10 T m.
  • We report an unusual phenomenon, peculiar sign reversals of the ground-state magnetic resonances and of the zero-dip resonance (Zeeman resonance at zero field) of optically pumped, alkali-metal vapors. These anomalies occur when a weak circularly polarized D1 laser light is tuned to pump atoms predominantly from the lower ground-state hyperfine multiplet. One can understand the signal reversals in a simple, semiquantitative way with reference to the spin-temperature distribution. Quantitative computer simulations are in excellent agreement with observations.
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  • Low detection sensitivity stemming from the weak polarization of nuclear spins is a primary limitation of magnetic resonance spectroscopy and imaging. Methods have been developed to enhance nuclear spin polarization but they typically require high magnetic fields, cryogenic temperatures or sample transfer between magnets. Here we report bulk, room-temperature hyperpolarization of 13C nuclear spins observed via high-field magnetic resonance. The technique harnesses the high optically induced spin polarization of diamond nitrogen vacancy centres at room temperature in combination with dynamic nuclear polarization. We observe bulk nuclear spin polarization of 6%, an enhancement of ~170,000 over thermal equilibrium. The signal ofmore » the hyperpolarized spins was detected in situ with a standard nuclear magnetic resonance probe without the need for sample shuttling or precise crystal orientation. In conclusion, hyperpolarization via optical pumping/dynamic nuclear polarization should function at arbitrary magnetic fields enabling orders of magnitude sensitivity enhancement for nuclear magnetic resonance of solids and liquids under ambient conditions.« less