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arXiv · 1607.00967

Gapped Excitations in the High-Pressure Antiferromagnetic Phase of URu$_2$Si$_2$

T. J. Williams·H. Barath·Z. Yamani·J. A. Rodriguez-Riviera·J. B. Leão·J. D. Garrett·G. M. Luke·W. J. L. Buyers·C. Broholm
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Abstract

We report a neutron scattering study of the magnetic excitation spectrum in each of the three temperature and pressure driven phases of URu$_2$Si$_2$. We find qualitatively similar excitations throughout the (H0L) scattering plane in the hidden order and large moment phases, with no changes in the $\hbarω$-widths of the excitations at the $Σ$ = (1.407,0,0) and $Z$ = (1,0,0) points, within our experimental resolution. There is, however, an increase in the gap at the $Σ$ point from 4.2(2) meV to 5.5(3) meV, consistent with other indicators of enhanced antiferromagnetism under pressure.

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T. J. Williams, H. Barath, Z. Yamani, J. A. Rodriguez-Riviera, J. B. Leão, J. D. Garrett, G. M. Luke, W. J. L. Buyers, C. Broholm. 2017-05-31. Gapped Excitations in the High-Pressure Antiferromagnetic Phase of URu$_2$Si$_2$. https://doi.org/10.1103/physrevb.95.195171

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