Code: MOD	Time Slot/Poster Number: 4:00-4:25	Session: Alternative Detection Methods
Time-Resolved, Optically-Detected NMR of Fluids at High Magnetic Field
Daniela Pagliero1; Wei Dong1; Dimitris Sakellariou2; Carlos Meriles1
1CUNY, New York, NY; 2CEA Saclay, Gif-sur-Yvette , France
Abstract
While the use of optical schemes to polarize and detect nuclear spins is well known, applications to date have been mostly restricted to atomic vapors and select condensed matter systems. Extension to organic fluids is of interest because the electron-mediated interaction between light and nuclear spins is sensitive to the chemical environment, thus offering opportunities for ‘light-assisted’ spectroscopic studies of different molecular moieties. This talk introduces recent results demonstrating time-resolved, high-field NMR of fluids using Optical Faraday Rotation. I will discuss various methodological aspects including the use of chemical-shift-resolved ODNMR spectra as a tool to measure hyperfine couplings of non-paramagnetic species. Also, I will briefly comment on extensions of this methodology that rely on high-finesse optical resonators to enhance sensitivity.

Code: MOD	Time Slot/Poster Number: 4:25-4:40	Session: Alternative Detection Methods
Coherent Radiofrequency Stark Spectroscopy of Quadrupolar Nuclei from POWER NMR
Matt Tarasek; James G. Kempf
Rensselaer Polytechnic Inst., Troy, NY
Abstract
NMR has potential as a powerful probe of electrostatics in a variety of applications. From device physics to biochemistry, E fields are crucial control factors whenever charges or dipoles are modulated. Electrostatic influences on NMR parameters are well accepted, yet there exist very few measures of NMR response to an E field. We observe rf quadrupolar Stark effects using POWER (perturbations observed with enhanced resolution) NMR. E fields oscillating at 2w0 induce DQ transitions in quadrupolar nuclei via Stark-distortion of the field gradient. Using POWER NMR, we obtain coherent Stark-induced NMR evolution: a quadrupole splitting proportional to the applied E field. Seminal results were obtained from crystalline GaAs. Simulations promise resolution of the same from CO moieties in proteins.

Code: MOD	Time Slot/Poster Number: 4:40-4:55	Session: Alternative Detection Methods
Origin of the "Dispersion-Like" Lineshape in Resistively Detected NMR in the Quantum Hall Effect: Evidence of the Skyrme Crystal?
Clifford R Bowers1; Guena M. Gusev2
1Chemistry Department, University of Florida, Gainesville, FL; 2Physics Department, University of Sao Paulo, Sao Paulo, Brazil
Abstract
Resistively detected NMR (RDNMR) at certain filling factors in the quantum Hall effect yields a peculiar “dispersion-like” lineshape and short nuclear spin-lattice relaxation times (c.a. 1s) at mK temperatures. In some reports, these observations have been attributed to the formation of a skyrme lattice. Here, new data will be presented examining the evolution of the lineshape and spin relaxation with magnetic field up to 16.1T. According to theory, quenching of the skyrme crystal, along with the associated Goldstone mode nuclear spin relaxation mechanism, is expected at the upper end of this range. Our results will be discussed in the context of the existing literature.

Code: MOD	Time Slot/Poster Number: 4:55-5:10	Session: Alternative Detection Methods
Finding the "Needle in a Haystack"--Evidence for Optically Relevant Defects (ORDs) in the OPNMR of GaAs
Sophia E. Hayes1; Kannan Ramaswamy1; Erika Sesti1; Katie Wentz1; Dustin Wheeler1; Christopher Stanton3; Gregory Salamo2
1Washington University, Saint Louis, MO; 2University of Arkansas, Fayetteville, AR; 3University of Florida, Gainesville, FL
Abstract
We will present spectroscopic evidence for one type of ORD that leads to nuclear polarization in Ga-69 OPNMR. By targeted doping of bulk GaAs (through molecular beam epitaxy), we have found that a substitutional defect in the GaAs lattice leads to lineshapes that are characteristic of the OPNMR phenomena (in the absence of this specific dopant, the effect was not observed). Alluding to the title, this is like finding a needle in a haystack. OPNMR is sensitive to defect sites that occupy one part in ~10,000,000, demonstrating the possible utility of OPNMR for analysis of very dilute or rare sites in a material.

Code: MOD	Time Slot/Poster Number: 5:10-5:35	Session: Alternative Detection Methods
Pulsed Electrically Detected Magnetic Resonance
Christoph Boehme
Department of Physics and Astronomy, Univ. of Utah, Salt Lake City, Utah
Abstract
Spin selection rules can influence charge transfer transitions in materials which govern electric currents. This effect allows electrically detected magnetic resonance (EDMR) spectroscopy, a method that provides experimental access to electron and nuclear spins that influence the conductivity of materials. EDMR has been used and explored since the 1960s almost exclusively as continuous wave experiment and only recently (2003) first pEDMR experiments were demonstrated. This presentation is aimed at giving an overview about the current state of the art and the capabilities of pEDMR. The technical and scientific challenges of pEDMR spectroscopy will be outlined before materials systems are discussed for which important and unique insights can be gained with pEDMR.

Code: MOD	Time Slot/Poster Number: 5:35-5:50	Session: Alternative Detection Methods
Hyperpolarized Xenon NMR and MRI Signal Amplification by Gas Extraction (Hyper-SAGE)
Xin Zhou1, 2; Dominic Graziani1; Alexander Pines1
1UC Berkeley & Lawrence Berkeley National Lab, Berkeley, CA; 2Wuhan Institute of Physics and Mathematics, Wuhan, China
Abstract
A novel method is reported for enhancing the sensitivity of NMR and MRI of dissolved xenon by detecting the signal after extraction to the gas phase. Hyperpolarized xenon signal amplification by gas extraction (Hyper-SAGE) has been demonstrated in both NMR spectra and magnetic resonance images with time-of-flight information. After extraction the xenon density can be further increased by several orders of magnitude by compression and/or liquefaction. Additionally, being a remote detection technique, the Hyper-SAGE effect is further enhanced in situations where the sample of interest would occupy only a small proportion of the traditional NMR receiver. Coupled with targeted xenon biosensors, Hyper-SAGE offers another path to highly sensitive molecular imaging of specific cell markers by detection of exhaled xenon gas.

Code: MOD	Time Slot/Poster Number: 5:50-6:05	Session: Alternative Detection Methods
Optimization of 4T Double Tuned Volume TEM Resonators for 1H/23Na Magnetic Resonance Imaging
Assunta Vitacolonna1; Antonello Sotgiu1, 2; Sandro Romanzetti3; Joerg Felder3; Jon N Shah3, 4; Marcello Alecci1
1Dip SDS, University of L'Aquila, L'Aquila, Italy; 2ITA srl, L'Aquila, Italy; 3Inst of Neuroscience and Medicine, Research Centre, Jülich, Germany; 4Fac. of Med., Dep. of Neurology, RWTH, Aachen University, Germany
Abstract
The Double-Tuned (DT) TEM resonator was especially developed for high field MRI. It was designed by disposing two sets of transmission line elements (TLEs) at the same radial position. It was noted that with this geometrical design the DT TEM resonator might give a rather limited frequency separation between at the high range modes producing shading artefacts and SNR loss. In this work we experimentally proved a method to optimize the frequency separation building an head size 4T DT TEM resonator for sodium and proton