@article {405, title = {Low field magnetic resonance images of polarized noble gases obtained with a dc superconducting quantum interference device}, journal = {Applied Physics Letters}, volume = {72}, year = {1998}, note = {Appl Phys LettZg930Times Cited:37Cited References Count:24}, month = {Apr 13}, pages = {1908-1910}, abstract = {

Using a low transition temperature superconducting quantum interference device as a detector, we have obtained magnetic resonance images of laser-polarized He-3 gas and solid Xe-129 at 4.2 K in magnetic fields as low as 0.54 mT (He-3) and 1 mT (Xe-129), corresponding to Larmor frequencies of 17.6 and 11.8 kHz, respectively. The experimental resolution of the images is similar to 500 mu m for He-3 ill the gas phase and similar to 950 mu m for Xe-129 in the solid state. (C) 1998 American Institute of Physics.

}, keywords = {mri}, isbn = {0003-6951}, doi = {Doi 10.1063/1.121223}, url = {://WOS:000073054300038}, author = {Augustine, M. P. and Wong-Foy, A. and Yarger, J. L. and Tomaselli, M. and Pines, A. and TonThat, D. M. and Clarke, J.} } @article {391, title = {Scalar and anisotropic J interactions in undoped InP: A triple-resonance NMR study}, journal = {Physical Review B}, volume = {58}, year = {1998}, note = {Phys Rev B125HUTimes Cited:29Cited References Count:40}, month = {Oct 1}, pages = {8627-8633}, abstract = {

The heteronuclear J-coupling tensor between nearest neighbor P-31 and In-113 spins in undoped InP is investigated by means of In-113--\>P-31 polarization transfer under rapid magic angle spinning (MAS). The scalar contribution can be measured directly and is found to have the value \J(iso)(P-31-In-113,In-115)\ = (225+/-10) Hz. The principal value of the traceless anisotropic J-coupling tensor (pseudodipolar coupling) is determined to be J(aniso)(P-31-In-113,In-115)= 2/3[J(parallel to)(P-31-In-113,In-115)-J(perpendicular to)(P-31-In-113,In-115)] = (813+/-50) or (1733+/-50) Hz, assuming axial symmetry with the principal axis parallel to the In-P bond. Our values deviate from those reported previously [M. Engelsberg and R. E. Norberg, Phys. Rev. B 5, 3395 (1972)] [based on a moment analysis of the P-31 resonance \J(iso)(31P-In-113,In-115)\ = 350 Hz and J(aniso)(P-31-In-113,In-115) = 1273 Hz], but confirm the postulate that the nearest neighbor P-31-In-113,In-115 magnetic dipolar and pseudodipolar interactions are of the same order of magnitude and partially cancel each other.

}, keywords = {solids}, isbn = {0163-1829}, doi = {Doi 10.1103/Physrevb.58.8627}, url = {://WOS:000076232100075}, author = {Tomaselli, M. and deGraw, D. and Yarger, J. L. and Augustine, M. P. and Pines, A.} } @article {408, title = {Low magnetic field dynamic nuclear polarization using a single-coil two-channel probe}, journal = {Review of Scientific Instruments}, volume = {68}, year = {1997}, note = {Rev Sci InstrumWp247Times Cited:4Cited References Count:29}, month = {Mar}, pages = {1527-1531}, abstract = {

We describe the design and construction of a single-coil, two-channel probe for the detection of low-field magnetic resonance using dynamic nuclear polarization (DNP). The high-frequency channel of the probe, which is used to saturate the electron spins, is tuned to the electron Larmor frequency, 75 MHz at 2.7 mT, and matched to 50 Omega. Low-field, H-1 nuclear magnetic resonance (NMR) is detected through the second, low-frequency channel at frequencies \<1 MHz. The performance of the probe was tested by measuring the DNP of protons in a manganese (II) chloride solution at 2.7 mT. At the proton NMR frequency of 120 kHz, the signal amplitude was enhanced over the value without DNP by a factor of about 200. (C) 1997 American Institute of Physics.

}, keywords = {nmr}, isbn = {0034-6748}, doi = {Doi 10.1063/1.1147641}, url = {://WOS:A1997WP24700033}, author = {TonThat, D. M. and Augustine, M. P. and Pines, A. and Clarke, J.} }