Zobrazeno 1 - 10
of 438
pro vyhledávání: '"Bossy, J."'
Autor:
Schmidt-Wellenburg, P., Bossy, J., Farhi, E., Fertl, M., Leung, K. K. H., Rahli, A., Soldner, T., Zimmer, O.
We have investigated experimentally the pressure dependence of the production of ultracold neutrons (UCN) in superfluid helium in the range from saturated vapor pressure to 20bar. A neutron velocity selector allowed the separation of underlying singl
Externí odkaz:
http://arxiv.org/abs/1506.07785
We report neutron scattering measurements on bcc solid $^{4}$% He. We studied the phonon branches and the recently discovered ''optic-like'' branch along the main crystalline directions. In addition, we discovered another, dispersionless "optic-like'
Externí odkaz:
http://arxiv.org/abs/cond-mat/0604477
Autor:
Pelleg, O., Shay, M., Lipson, S. G., Polturak, E., Bossy, J., Marmeggi, J. C., Kentaro, H., Farhi, E., Stunault, A.
We report neutron diffraction studies of low density bcc and hcp solid 4He. In the bcc phase, we observed a continuous dynamical behaviour involving macroscopic structural changes of the solid. The dynamical behaviour takes place in a cell full of so
Externí odkaz:
http://arxiv.org/abs/cond-mat/0505763
We report neutron scattering measurements of the phonons in bcc solid 4He. In general, only 3 accoustic phonon branches should exist in a monoatomic cubic crystal. In addition to these phonon branches, we found a new ''optic-like'' mode along the [11
Externí odkaz:
http://arxiv.org/abs/cond-mat/0203086
Autor:
Sidis, Y., Bourges, P., Keimer, B., Regnault, L. P., Bossy, J., Ivanov, A., Hennion, B., Gautier-Picard, P., Collin, G.
Nonmagnetic Zn impurities are known to strongly suppress superconductivity. We review their effects on the spin excitation spectrum in $\rm YBa_2Cu_3O_{7}$, as investigated by inelastic neutron scattering measurements.
Comment: Proceedings of Ma
Comment: Proceedings of Ma
Externí odkaz:
http://arxiv.org/abs/cond-mat/0006265
Publikováno v:
Science, {\bf 288} p 1234 (2000)
A comprehensive inelastic neutron scattering study of magnetic excitations in the near-optimally doped high-temperature superconductor ${\rm YBa_{2}Cu_{3}O_{6.85}}$ is presented. The spin correlations in the normal state are commensurate with the cry
Externí odkaz:
http://arxiv.org/abs/cond-mat/0006086
Autor:
Sidis, Y., Bourges, P., Fong, H. F., Keimer, B., Regnault, L. P., Bossy, J., Ivanov, A., Hennion, B., Gautier-Picard, P., Collin, G., Millius, D. L., Aksay, I. A.
Publikováno v:
Phys. Rev. Lett. 84, 5900 (2000).
The influence of magnetic (S=1) and nonmagnetic (S=0) impurities on the spin dynamics of an optimally doped high temperature superconductor is compared in two samples with almost identical superconducting transition temperatures: YBa$_2$(Cu$_{0.97}$N
Externí odkaz:
http://arxiv.org/abs/cond-mat/9912214
Autor:
Fong, H. F., Bourges, P., Sidis, Y., Regnault, L. P., Bossy, J., Ivanov, A., Milius, D. L., Aksay, I. A., Keimer, B.
Publikováno v:
Phys. Rev. B 61, 14773 (2000)
We report a comprehensive polarized and unpolarized neutron scattering study of the evolution of the dynamical spin susceptibility with temperature and doping in three underdoped single crystals of the \YBCO{6+x} high temperature superconductor: \YBC
Externí odkaz:
http://arxiv.org/abs/cond-mat/9910041
Autor:
Bourges, Ph., Sidis, Y., Fong, H. F., Keimer, B., Regnault, L. P., Bossy, J., Ivanov, A. S., Milius, D. L., Aksay, I. A.
Publikováno v:
High Temperature Superconductivity Edited by S.E. Barnes {\it et al} 207-212 (CP483 American Institute of Physics, Amsterdam, 1999) .
Key features of antiferromagnetic dynamical correlations in high-$T_C$ superconductors cuprates are discussed. In underdoped regime, the sharp resonance peak, occuring exclusively in the SC state, is accompanied by a broader contribution located arou
Externí odkaz:
http://arxiv.org/abs/cond-mat/9902067
Autor:
Fong, H. F., Bourges, P., Sidis, Y., Regnault, L. P., Bossy, J., Ivanov, A., Milius, D. L., Aksay, I. A., Keimer, B.
Publikováno v:
Phys. Rev. Lett. 82, 1939 (1999)
The magnetic excitation spectrum of a YBa_2 Cu_3 O_7 crystal containing 0.5% of nonmagnetic (Zn) impurities has been determined by inelastic neutron scattering. Whereas in the pure system a sharp resonance peak at E ~ 40 meV is observed exclusively b
Externí odkaz:
http://arxiv.org/abs/cond-mat/9812047