Thurber KR, Imai T, Saitoh T, Azuma M, Takano M, Chou FC
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.
Phys Rev Lett. 2000 Jan 17;84(3):558-61. doi: 10.1103/PhysRevLett.84.558.
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).
我们利用63Cu核四极共振在S = 1 / 2的三腿梯子状化合物Sr2Cu3O5中探测了高达725 K的自旋-自旋关联。我们给出的实验证据表明，在300 K以下，弱的层间耦合导致自旋-自旋关联长度ξ从准一维（ξ约为1 / T）到各向异性二维 regime（ξ约为exp2πρ(s)/T，其中2πρ(s) = 290±30 K是有效自旋刚度）的维度交叉。
