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Incommensurate Magnetic Fluctuations in YBa2Cu3O6.6

Pengcheng Dai·H. A. Mook·F. Dogan
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Abstract

We use inelastic neutron scattering to demonstrate that at low temperatures, the low frequency magnetic fluctuations in YBa_2Cu_3O_{6.6} ($T_c=62.7$ K) are incommensurate, being found at positions displaced by $\pmδ$ ($0.057\pm 0.006$ r.l.u.) along the $[π,π]$ direction from the wave vector $(π,π)$ associated with the antiferromagnetic order of the parent insulator, YBa_2Cu_3O_{6}. The dynamical susceptibility $χ''(q,ω)$ at the incommensurate positions increases on cooling below $T_c$, accompanied by a suppression of magnetic fluctuations at the commensurate points.

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Pengcheng Dai, H. A. Mook, F. Dogan. 1997-07-10. Incommensurate Magnetic Fluctuations in YBa2Cu3O6.6. https://doi.org/10.1103/physrevlett.80.1738

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