https://doi.org/10.1007/s100510050297
New slow and short range magnetic correlations in superconducting _a2_xSxCuO4
Laboratoire Léon Brillouin,
CE-SACLAY, 91191 Gif-sur-Yvette, France and
Laboratoire de Chimie des solides (URA 446 CNRS) , Université
Paris-Sud, Orsay, France
Corresponding author: a spetit@bali.saclay.cea.fr
Received:
3
September
1997
Revised:
21
November
1997
Accepted:
26
January
1998
Published online: 15 May 1998
Inelastic neutron scattering measurements have been
performed on high quality single crystals of
in
order to study the spin dynamics of this compound.
In addition to the well-established incommensurate
magnetic response, we show the existence of a new
set of low energy excitations present in the whole
superconducting region of the phase diagram. This
new feature of the dynamical cross section is
characterized, below about 10 K, by very short
range (
lattice spacing) antiferromagnetic
correlations and by a low energy
scale of
meV.
At higher temperatures these fluctuations become
nearly Q-independent. Different possible origins of
these new spin correlations are discussed.
PACS: 74.25.Ha – Magnetic properties / 74.72.Dn – La-based cuprates / 78.70.Nx – Neutron inelastic scattering
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998