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Related papers: Spin Transition in the Half-Filled Landau Level

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$^1$H nuclear spin-lattice relaxation and Dynamic Nuclear Polarization (DNP) have been studied in amorphous samples of trehalose sugar doped with TEMPO radicals by means of mechanical milling, in the 1.6 K $\div$ 4.2 K temperature range.…

Recently, Pang et al reported a novel polarization transfer scheme applicable to three-spin systems, whereby a rotating-frame NMR analogue of the cross effect could transfer polarization between; e.g., two 13Cs and an 15N in a single…

Quantum Physics · Physics 2026-04-21 Sundaresan Jayanthi , Adonis Lupulescu , Julia Grinshtein , Lucio Frydman

The longitudinal resistivity at transitions between integer quantum Hall states in two-dimensional electrons confined to AlAs quantum wells is found to depend on the spin orientation of the partially-filled Landau level in which the Fermi…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 K. Vakili , Y. P. Shkolnikov , E. Tutuc , N. C. Bishop , E. P. De Poortere , M. Shayegan

We suggest a new spin orientation mechanism for localized electrons: $dynamic~electron~spin~polarization~provided~by~nuclear~spin~fluctuations$. The angular momentum for the electrons is gained from the nuclear spin system via the hyperfine…

Mesoscale and Nanoscale Physics · Physics 2020-10-14 D. S. Smirnov , T. S. Shamirzaev , D. R. Yakovlev , M. Bayer

We analyze the phase transition between spin-singlet and spin-polarized states which occurs at $\nu=2/3$. The basic strategy is to use adiabatic flux-trading arguments to relate this transition to the analogous transition at $\nu=2$. The…

Condensed Matter · Physics 2009-10-28 Chetan Nayak , Frank Wilczek

Dynamic nuclear polarisation (DNP) refers to a class of techniques used to increase the signal in nuclear magnetic resonance measurements by transferring spin polarisation from ensembles of highly polarised electrons to target nuclear…

Quantum Physics · Physics 2020-12-24 L. T. Hall , D. A. Broadway , A. Stacey , D. A. Simpson , J-P. Tetienne , L. C. L. Hollenberg

From general arguments, that are valid for spin models with sufficiently short-range interactions, we derive strong constraints on the excitation spectrum across a continuous phase transition at zero temperature between a magnetic and a…

Strongly Correlated Electrons · Physics 2009-11-11 Leonardo Spanu , Federico Becca , Sandro Sorella

Double layer two-dimensional electron systems at high perpendicular magnetic field are used to realize magnetic tunnel junctions in which the electrons at the Fermi level in the two layers have either parallel or anti-parallel spin…

Mesoscale and Nanoscale Physics · Physics 2017-05-10 J. P. Eisenstein , L. N. Pfeiffer , K. W. West

The spin-nematic phase is an intriguing state of matter that lacks usual long-range dipolar order, yet it exhibits higher multipolar order. This makes its detection extremely difficult and controversial. Recently, nuclear magnetic resonance…

Strongly Correlated Electrons · Physics 2020-08-10 M. Pregelj , A. Zorko , D. Arčon , M. Klanjšek , O. Zaharko , S. Krämer , M. Horvatić , A. Prokofiev

Local-susceptibility measurements via the NMR shifts of $^{31}$P and $^{51}$V nuclei in the high-pressure phase of (VO)$_{2}$P$_{2}$O$_{7}$ confirmed the existence of a unique alternating antiferromagnetic chain with a zero-field spin gap…

Strongly Correlated Electrons · Physics 2007-05-23 J. Kikuchi , K. Motoya , T. Saito , M. Azuma , M. Takano

We applied the recently developed technique of force-detected nuclear magnetic resonance (NMR) to observe 71Ga, 69Ga, and 75As in GaAs. The nuclear spin-lattice relaxation time is 21$\pm$5 min for 69Ga at $\sim 5$ K and 4.6 Tesla. We have…

Materials Science · Physics 2009-11-07 Kent R. Thurber , Lee E. Harrell , Raul Fainchtein , Doran D. Smith

Low-temperature, electronic transport in Landau levels N>1 of a two-dimensional electron system is strongly anisotropic. At half-filling of either spin level of each such Landau level the magnetoresistance either collapses to form a deep…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 R. R. Du , D. C. Tsui , H. L. Stormer , L. N. Pfeiffer , K. W. Baldwin , K. W. West

Half-filled Landau levels host an emergent Fermi-liquid which displays an instability towards pairing, culminating in a gapped even-denominator fractional quantum Hall ground state. While this pairing may be probed by tuning the…

Mesoscale and Nanoscale Physics · Physics 2019-02-19 J. Falson , D. Tabrea , D. Zhang , I. Sodemann , Y. Kozuka , A. Tsukazaki , M. Kawasaki , K. von Klitzing , J. H. Smet

Nuclear spins are polarized electrically in a breakdown regime of an odd-integer quantum Hall effect (QHE). Electron excitation to the upper Landau subband with the opposite spin polarity flips nuclear spins through the hyperfine…

Mesoscale and Nanoscale Physics · Physics 2008-07-04 M. Kawamura , H. Takahashi , S. Masubuchi , Y. Hashimoto , S. Katsumoto , K. Hamaya , T. Machida

In this work, we report nuclear magnetic resonance (NMR) combined with density functional theory (DFT) studies of the transition metal dichalcogenide ZrTe$_2$. The measured NMR shift anisotropy reveals a quasi-2D behavior connected to a…

Strongly Correlated Electrons · Physics 2020-10-28 Yefan Tian , Nader Ghassemi , Joseph H. Ross

We study the nuclear magnetic resonance (NMR) spin-lattice relaxation rate $1/T_1$ in random one-dimensional spin chains as function of the temperature and disorder strength. In the zero temperature limit, the system displays a…

Strongly Correlated Electrons · Physics 2019-06-05 Maxime Dupont

We study the critical spin-polarization energy ($\alpha_{\rm C}$) above which fractional quantum Hall states in two-dimensional electron systems confined to symmetric GaAs quantum wells become fully spin-polarized. We find a significant…

Mesoscale and Nanoscale Physics · Physics 2014-09-23 Yang Liu , S. Hasdemir , A. Wójs , J. K. Jain , L. N. Pfeiffer , K. W. West , K. W. Baldwin , M. Shayegan

Excitation modes in the range $2/5 \geq \nu \geq 1/3$ of the fractional quantum Hall regime are observed by resonant inelastic light scattering. Spectra of spin reversed excitations suggest a structure of lowest spin-split Landau levels of…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Irene Dujovne , A. Pinczuk , Moonsoo Kang , B. S. Dennis , L. N. Pfeiffer , W. K. West

Nuclear spin coherence and relaxation dynamics of all constituent isotopes of an n-doped CdTe/(Cd,Mg)Te quantum well structure are studied employing optically detected nuclear magnetic resonance. Using time-resolved pump-probe Faraday…

Mesoscale and Nanoscale Physics · Physics 2019-04-04 E. Evers , T. Kazimierczuk , F. Mertens , D. R. Yakovlev , G. Karczewski , T. Wojtowicz , J. Kossut , M. Bayer , A. Greilich

We have observed an electronic energy level crossing in a molecular nanomagnet (MNM) using muon-spin relaxation. This effect, not observed previously despite several muon studies of MNM systems, provides further evidence that the spin…

Strongly Correlated Electrons · Physics 2015-05-27 T. Lancaster , J. S. Moeller , S. J. Blundell , F. L. Pratt , P. J. Baker , T. Guidi , G. A. Timco , R. E. P. Winpenny