https://doi.org/10.1007/s100510050850
Spin dynamics in hole-doped two-dimensional S = 1/2 Heisenberg antiferromagnets: 63Cu NQR relaxation in La2-xSrxCuO4 for x≤0.004
1
Department of Physics "A. Volta",
Unità INFM di Pavia,
Via Bassi 6, 27100 Pavia, Italy
2
Ames Laboratory-USDOE and
Department of Physics and Astronomy, ISU, Ames, Iowa 50011, USA
Corresponding author: a carretta@pv.infn.it
Received:
13
August
1998
Revised:
7
December
1998
Published online: 15 July 1999
The effects on the correlated Cu2+
S = 1/2 spin dynamics
in the paramagnetic phase of La2-xSrxCuO4 (for ) due to
the injection of holes are studied by means of 63Cu NQR spin-lattice relaxation time T1
measurements. The results are discussed in the framework of the connection between T1 and
the in-plane magnetic correlation length
.
It is found that at high temperatures the system remains in the renormalized classical regime,
with a spin stiffness constant
reduced by small doping to an extent larger than the
one due to Zn doping. For
the effect of doping on
appears to
level off.
The values for
derived from T1 for
K are much larger
than the ones estimated from the temperature behavior of
sublattice magnetization in the ordered phase (
).
It is argued that these features are consistent with
the hypothesis of formation of stripes of microsegregated holes.
PACS: 76.60.-k – Nuclear magnetic resonance and relaxation / 74.20.Mn – Nonconventional mechanisms (spin fluctuations, polarons and bipolarons, resonating valence bond model, anyon mechanism, marginal Fermi liquid, Luttinger liquid, etc.) / 75.40.Gb – Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1999