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Surprising Loss of Three-Dimensionality in Low-Energy Spin Correlations on Approaching Superconductivity in Fe1+yTe1-xSex
Published
Author(s)
Zhijun Xu, J. A. Schneeloch, Jinsheng Wen, B. L. Winn, G. E. Granroth, Yang Zhao, Genda Gu, I. Zaliznyak, J. M. Tranquada, R. J. Birgeneau, Guangyong Xu
Abstract
We report inelastic neutron scattering measurements of low energy (hwapproximately less than} 10 meV) magnetic excitations in the "11" system Fe1+yTe1-xSex. The spin correlations are two-dimensional (2D) in the superconducting samples at low temperature, but appear much more three-dimensional when the temperature rises well above Tc 15K, with a clear increase of the (dynamic) spin correlation length perpendicular to the Fe planes. The spontaneous change of dynamic spin correlations from 2D to 3D on warming is unexpected and and cannot be naturally explained when only the spin degree of freedom is considered. Our results suggest that the low temperature physics in the "11" system, in particular the evolution of low energy spin excitations towards superconducting pairing, is driven by changes in orbital correlations.
Xu, Z.
, Schneeloch, J.
, Wen, J.
, Winn, B.
, Granroth, G.
, Zhao, Y.
, Gu, G.
, Zaliznyak, I.
, Tranquada, J.
, Birgeneau, R.
and Xu, G.
(2017),
Surprising Loss of Three-Dimensionality in Low-Energy Spin Correlations on Approaching Superconductivity in Fe<sub>1+y</sub>Te<sub>1-x</sub>Se<sub>x</sub>, Physical Review B, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=923502
(Accessed October 22, 2025)