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CreatorTitleDescriptionSubjectDate
1 Ailion, David CharlesNuclear magnetic resonance in LiF: a single nuclear-dipolar-spin temperature in crystals with more than one spin speciesIn a crystal containing more than one species of nuclear spin in a large dc magnetic field, the secular dipolar interactions between all spins, unlike as well as like, form a single reservoir described by a single spin temperature. We demonstrated this concept with experiments on LiF. In particula...Spin species; Spin-lattice relaxation; NMR; Nuclear magnetic resonance1977
2 Symko, Orest GeorgeAcoustic approach to thermal management: miniature thermoacoustic enginesAn acoustic approach to thermal management in electronics can be efficient and it can be directly interfaced with electronic devices. It is based on two types of thermoacoustic heat engines, which are being developed for microcircuit applications. One type of device, the prime mover, converts heat t...Thermoacoustic engines; Thermal management2006
3 Saam, Brian; Laicher, GernotLiquid hyperpolarized 129Xe produced by phase exchange in a convection cellWe present a method for the production of liquid hyperpolarized 129Xe that employs spin-exchange optical pumping in the gas phase and subsequent phase exchange with a column of xenon liquid. A convection loop inside the sealed glass cell allows efficient transfer of magnetization between the gas an...Liquid hyperpolarized 129Xe; Phase exchange; Spin-exchange optical pumping; SEOP; NMR; Spin polarization2004
4 Ailion, David CharlesNMR methods for identifying and studying diffusion of different spin species in heteronuclear systemsWe introduce a new dipolar relaxation lime TU)' which characterizes the spin-lattice relaxation of secular dipolar interactions in the presence of a large rf field. Measurements of T]D' are particularly useful for studying slow atomic motions in muitispin systems, since such measurements enable us ...NMR; Nuclear magnetic resonance; Nuclear-spin species; Diffusion; Molecular rotations1978
5 Mishchenko, EugenePseudospin ferromagnetism in double-quantum-wire systemsWe propose that a pseudospin ferromagnetic (i.e., interwire coherent) state can exist in a system of two parallel wires of finite width in the presence of a perpendicular magnetic field. This novel quantum many-body state appears when the interwire distance decreases below a certain critical value ...Coulomb drag; Quantum wires2005-08
6 Mattis, Daniel C.Extinction of antiferromagnetism by holes in CuO2The introduction of a sufficient number of holes into antiferromagnetic planes of Cu02 in La-Cu-O and Y-Ba-Cu-O causes antiferromagnetism to disappear at a critical density xc, beyond which superconductivity occurs. We investigate two competing tendencies, which determine the dependence of xc on the...Antiferromagnets1991-08
7 Saam, Brian3He spin exchange cells for magnetic resonance imagingWe present a protocol for the consistent fabrication of glass cells to provide hyperpolarized (HP) 3He for pulmonary magnetic resonance imaging. The method for producing HP 3He is spin-exchange optical pumping. The valved cells must hold of order 1 atm.L of gas at up to 15 atm pressure. Because char...3He; Spin exchange cells; Hyperpolarized 3He; Pulmonary magnetic resonance imaging; Spin-exchange optical pumping; SEOP; Glass cells2002
8 Ailion, David CharlesNew NMR techniques to study diffusion in multispin crystalsWe present a new NMR method for studying slow diffusion in multispin systems. With this method we can vary the effect of a particular spin species' motion relative to the others, thus enabling us to separate and identify the component motions. We present a new pulse sequence for measuring T1L', a ge...NMR; Nuclear magnetic resonance; Crystals; Nuclear-spin species; Diffusion; Molecular rotations1977
9 Ailion, David CharlesNMR in lithium metal: thermal mixingWe present a calculation of the thermal mixing rate t~ 1 between nuclear Zeeman and dipolar reservoirs in the presence of large rf fields. We applied this calculation to slow-motion diffusion in lithium metal. In particular, we measured the rotating frame spin-lattice relaxation time Tl p as a funct...NMR; Nuclear magnetic resonance; Lattices; Relaxation time1977
10 Gerton, JordanLaser-free slow atom sourceA slow atom source, which does not rely on lasers, has been developed and characterized. The device, acting as an atomic low-pass velocity filter, utilizes permanent magnets to passively select the slow atoms present in a thermal atomic beam. Slow atoms are guided along a curved, conduction-limite...1999-11
11 Mishchenko, EugeneGeneration of spin current by Coulomb dragCoulomb drag between two quantum wires is exponentially sensitive to the mismatch of their electronic densities. The application of a magnetic field can compensate this mismatch for electrons of opposite spin directions in different wires. The resulting enhanced momentum transfer leads to the conv...Spin current; Coulomb drag; Quantum wires2006-12
12 Lupton, John MarkNonequilibrium polariton dynamics in organic microcavitiesMicrocavities containing a J-aggregate forming organic dye were prepared in the strong-coupling regime. Changing the position of the neat organic films within the microcavity allows a tuning of the giant Rabi splitting observed. We set the Rabi splitting to 25 meV and study the thermal activation o...Nonequilibrium polariton dynamics; Organic microcavities; Optical microcavities; Rabi splitting; Light-matter interactions; Arrhenius activation2002-08
13 Bromley, Benjamin C.Binary disruption by massive black holes: hypervelocity stars, S stars, and tidal disruption eventsWe examine whether disrupted binary stars can fuel black hole growth. In this mechanism, tidal disruption produces a single hypervelocity star (HVS) ejected at high velocity and a former companion star bound to the black hole. After a cluster of bound stars forms, orbital diffusion allows the black ...2012-01-01
14 Mattis, Daniel C.Localized magnetic moments in dilute metallic alloys: correlation effectsWe discuss qualitatively the importance of the correlation energy in determining the ground state of a metal with an impurity atom. For a single, partly occupied impurity Estate orbital, the correlation energy acts to prevent the appearance of a nonvanishing ground-state spin, so that this simple no...Magnetic moments; Metallic alloys; Correlation energy; Magnetic impurities; Orbital degeneracy1965-11
15 Vardeny, Zeev ValentineOptical probes of ∏-conjugated polymer blends with strong acceptor moleculesWe used a variety of optical probes to study the primary and long-lived photoexcitations in blends of polyphenylene-vinylene derivative poly(2-methoxy-5(2'-ethyl)hexoxy-phenylenevinylene) (MEH-PPV) with various concentrations of a strong electron-acceptor molecule 2,4,7-trinitro-9-fluorenone (TNF...pi-conjugated polymers; pi-conjugated polymer blends; Acceptor molecules; Optical probes; Photoexcitations; MEH-PPV; Electron acceptors; Organic solar cells2009-05
16 Bromley, Benjamin C.Variations on debris disks: icy planet formation at 30-150 AU for 1-3 M. main-sequence starsWe describe calculations for the formation of icy planets and debris disks at 30-150 AU around 1-3 M. stars. Debris disk formation coincides with the formation of planetary systems. As protoplanets grow, they stir leftover planetesimals to large velocities. A cascade of collisions then grinds the l...Icy planets; Planet formation; Debris disks; Main-sequence stars2008
17 Bromley, Benjamin C.Rise and fall of debris disks: MIPS observations of h and chi Persei and the evolution of mid-IR emission from planet formationWe describe Spitzer MIPS observations of the double cluster, h and X Persei, covering a 0.6 deg2 area surrounding the cores of both clusters. The data are combined with IRAC and 2MASS data to investigate 616 sources from 1.25Y24 m. We use the long-baseline Ks ½24 color to identify two population...Infrared circumstellar matter; Open clusters and associations stars: Individual (NGC 869, NGC 884) planetary systems: Formation, planetary systems: Protoplanetary disks2008
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