63Cu NQR evidence of dimensional crossover to anisotropic 2D regime in S = 1 / 2 three-Leg ladder Sr2Cu3O5
We probed spin-spin correlations up to 725 K with 63Cu nuclear quadrupole resonance in the S = 1 / 2 three-leg ladder Sr2Cu3O5. We present experimental evidence that below 300 K weak interladder coupling causes dimensional crossover of the spin-spin correlation length xi from the quasi-1D (xi approximately 1 / T) to the anisotropic 2D regime ( xi approximately exp2pirho(s) / T, where 2pirho(s) = 290+/-30 K is the effective spin stiffness).
Thurber
KR
Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 and Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Imai
T
Saitoh
T
Azuma
M
Takano
M
Chou
FC