Mesoscopic correlations in Tb2Ti2O7 spin liquid

Article

关键词: MAGNETIC MONOPOLES;    DYNAMICS;    FIELD;   

DOI  :  10.1103/PhysRevB.92.144412

来源: SCIE

【 摘 要 】

We have studied the spin correlations with k = (1/2, 1/2, 1/2) propagation vector, which appear below 0.4 K in Tb2Ti2O7 spin liquid by combining powder neutron diffraction and specific heat on Tb2+xTi2-xO7+y samples with x = 0, 0.01, and -0.01. The k = (1/2, 1/2, 1/2) order clearly appears on all neutron patterns by subtracting a pattern at 1.2(1) K. Refining the subtracted patterns at 0.07 K yields two possible spin structures, with spin-ice-like and monopolelike correlations. Mesoscopic correlations involve Tb moments of 1 to 2 mu(B) ordered on a length scale of about 20 angstrom. In addition, long-range order involving a small spin component of 0.1 to 0.2 mu(B) is detected for the x = 0 and 0.01 samples showing a peak in the specific heat. Comparison with previous single-crystal data suggests that the (1/2, 1/2, 1/2) order settles in through nanometric spin textures with dominant spin-ice character and correlated orientations, analogous to nanomagnetic twins.

【 授权许可】

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