Search Results - "Lefmann, K"

Distinct Nature of Static and Dynamic Magnetic Stripes in Cuprate Superconductors by Jacobsen, H, Holm, S L, Lăcătuşu, M-E, Rømer, A T, Bertelsen, M, Boehm, M, Toft-Petersen, R, Grivel, J-C, Emery, S B, Udby, L, Wells, B O, Lefmann, K

“…We present detailed neutron scattering studies of the static and dynamic stripes in an optimally doped high-temperature superconductor, La_{2}CuO_{4+y}. We…”
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Field-induced Tomonaga-Luttinger liquid phase of a two-leg spin-1/2 ladder with strong leg interactions by Hong, Tao, Kim, Y H, Hotta, C, Takano, Y, Tremelling, G, Turnbull, M M, Landee, C P, Kang, H-J, Christensen, N B, Lefmann, K, Schmidt, K P, Uhrig, G S, Broholm, C

“…We study the magnetic-field-induced quantum phase transition from a gapped quantum phase that has no magnetic long-range order into a gapless phase in the…”
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Antiferromagnetic order induced by an applied magnetic field in a high-temperature superconductor by Lake, B, Rønnow, H. M, Christensen, N. B, Aeppli, G, Lefmann, K, McMorrow, D. F, Vorderwisch, P, Smeibidl, P, Mangkorntong, N, Sasagawa, T, Nohara, M, Takagi, H, Mason, T. E

“…One view of the high-transition-temperature (high-Tc) copper oxide superconductors is that they are conventional superconductors where the pairing occurs…”
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Spins in the Vortices of a High-Temperature Superconductor by Lake, B., Aeppli, G., Clausen, K. N., McMorrow, D. F., Lefmann, K., Hussey, N. E., Mangkorntong, N., Nohara, M., Takagi, H., Mason, T. E., Schröder, A.

“…Neutron scattering is used to characterize the magnetism of the vortices for the optimally doped high-temperature superconductor La2-xSrxCuO 4(x = 0.163) in an…”
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Optimizing a neutron-beam focusing device for the direct geometry time-of-flight spectrometer TOFTOF at the FRM II reactor source by Rasmussen, N.G., Simeoni, G.G., Lefmann, K.

“…A dedicated beam-focusing device has been designed for the direct geometry thermal-cold neutron time-of-flight spectrometer TOFTOF at the neutron facility FRM…”
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Non-destructive characterisation of dopant spatial distribution in cuprate superconductors by Ţuţueanu, A.-E., Sales, M., Eliasen, K.L., Lǎcǎtuşu, M.-E., Grivel, J.-C., Kardjilov, N., Manke, I., Krzyzagorski, M., Sassa, Y., Andersson, M.S., Schmidt, S., Lefmann, K.

“…highlights•Polarised neutron imaging used to map doping variations in cuprate superconductors.•Non-destructive determination of doping in bulk superconducting…”
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Q-dependent electron-phonon coupling induced phonon softening and non-conventional critical behavior in the CDW superconductor LaPt2Si2 by Nocerino, E., Stuhr, U., San Lorenzo, I., Mazza, F., Mazzone, D.G., Hellsvik, J., Hasegawa, S., Asai, S., Masuda, T., Itoh, S., Minelli, A., Hossain, Z., Thamizhavel, A., Lefmann, K., Sassa, Y., Månsson, M.

“…This paper reports the first experimental observation of phonons and their softening on single crystalline LaPt2Si2 via inelastic neutron scattering. From the…”
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Magnetic-field-induced soft-mode quantum phase transition in the high-temperature superconductor La1.855Sr0.145CuO4: an inelastic neutron-scattering study by Chang, J, Christensen, N B, Niedermayer, Ch, Lefmann, K, Rønnow, H M, McMorrow, D F, Schneidewind, A, Link, P, Hiess, A, Boehm, M, Mottl, R, Pailhés, S, Momono, N, Oda, M, Ido, M, Mesot, J

“…Inelastic neutron-scattering experiments on the high-temperature superconductor La1.855Sr0.145CuO4 reveal a magnetic excitation gap Delta that decreases…”
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Dynamic rotor mode in antiferromagnetic nanoparticles by Lefmann, K., Jacobsen, H., Garde, J., Hedegård, P., Wischnewski, A., Ancona, S. N., Jacobsen, H. S., Bahl, C. R. H., Kuhn, L. Theil

“…We present experimental, numerical, and theoretical evidence for an unusual mode of antiferromagnetic dynamics in nanoparticles. Elastic neutron scattering…”
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Prediction of beam hardening artefacts in computed tomography using Monte Carlo simulations by Thomsen, M., Knudsen, E.B., Willendrup, P.K., Bech, M., Willner, M., Pfeiffer, F., Poulsen, M., Lefmann, K., Feidenhans’l, R.

“…We show how radiological images of both single and multi material samples can be simulated using the Monte Carlo simulation tool McXtrace and how these images…”
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Hydrogen Dynamics in Na3AlH6:  A Combined Density Functional Theory and Quasielastic Neutron Scattering Study by Voss, J, Shi, Q, Jacobsen, H. S, Zamponi, M, Lefmann, K, Vegge, T

“…Understanding the elusive catalytic role of titanium-based additives on the reversible hydrogenation of complex hydrides is an essential step toward developing…”
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CAMEA ESS – The continuous angle multi-energy analysis indirect geometry spectrometer for the European Spallation Source by Freeman, P.G., Birk, J.O., Markó, M., Bertelsen, M., Larsen, J., Christensen, N.B., Lefmann, K., Jacobsen, J., Niedermayer, Ch, Juranyi, F., Ronnow, H.M.

“…The CAMEA ESS neutron spectrometer is designed to achieve a high detection efficiency in the horizontal scattering plane, and to maximize the use of the long…”
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Extended quantum critical phase in a magnetized spin-1/2 antiferromagnetic chain by Stone, M B, Reich, D H, Broholm, C, Lefmann, K, Rischel, C, Landee, C P, Turnbull, M M

“…Measurements are reported of the magnetic field dependence of excitations in the quantum critical state of the spin S=1/2 linear chain Heisenberg…”
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Point defect dynamics in sodium aluminum hydrides—A combined quasielastic neutron scattering and density functional theory study by Shi, Q., Voss, J., Jacobsen, H.S., Lefmann, K., Zamponi, M., Vegge, T.

“…Understanding the catalytic role of titanium-based additives on the reversible hydrogenation of complex metal hydrides is an essential step towards developing…”
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Three-dimensionality of field-induced magnetism in a high-temperature superconductor by Lake, B, Lefmann, K, Christensen, N. B, Aeppli, G, McMorrow, D. F, Ronnow, H. M, Vorderwisch, P, Smeibidl, P, Mangkorntong, N, Sasagawa, T, Nohara, M, Takagi, H

“…Many physical properties of high-temperature superconductors are two-dimensional phenomena derived from their square-planar CuO2 building blocks. This is…”
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Interparticle interactions in composites of nanoparticles of ferrimagnetic (γ-Fe2O3) and antiferromagnetic (CoO, NiO) materials by FRANDSEN, C, OSTENFELD, C. W, XU, M, JACOBSEN, C. S, KELLER, L, LEFMANN, K, MØRUP, S

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McStas-model of the delft SESANS by Knudsen, E., Udby, L., Willendrup, P.K., Lefmann, K., Bouwman, W.G.

“…We present simulation results taking first virtual data from a model of the Spin-Echo Small Angle Scattering (SESANS) instrument situated in Delft, in the…”
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Spin gap and magnetic coherence in a clean high-temperature superconductor by Lake, B, Aeppli, G, Mason, T. E, Schröder, A, McMorrow, D. F, Lefmann, K, Isshiki, M, Nohara, M, Takagi, H, Hayden, S. M

“…A notable aspect of high-temperature superconductivity in the copper oxides is the unconventional nature of the underlying paired-electron state. A direct…”
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Spin dynamics of the 2D spin 1/2 quantum antiferromagnet copper deuteroformate tetradeuterate (CFTD) by Rønnow, H M, McMorrow, D F, Coldea, R, Harrison, A, Youngson, I D, Perring, T G, Aeppli, G, Syljuåsen, O, Lefmann, K, Rischel, C

“…The magnetic excitation spectrum in the two-dimensional (2D) S = 1/2 Heisenberg antiferromagnet copper deuteroformate tetradeuterate has been measured for…”
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Monte Carlo simulations of neutron-scattering instruments using McStas by Nielsen, K, Lefmann, K

“…Monte Carlo simulations have become an essential tool for improving the performance of neutron-scattering instruments, since the level of sophistication in the…”
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