High energy spin excitations in YBa_2 Cu_3 O_{6.5}

Ph. Bourges; H. F. Fong; L. P. Regnault; J. Bossy; C. Vettier; D. L. Milius; I. A. Aksay; B. Keimer

doi:10.1103/physrevb.56.r11439

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High energy spin excitations in YBa_2 Cu_3 O_{6.5}

Ph. Bourges·H. F. Fong·L. P. Regnault·J. Bossy·C. Vettier·D. L. Milius·I. A. Aksay·B. Keimer

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Abstract

Inelastic neutron scattering has been used to obtain a comprehensive description of the absolute dynamical spin susceptibility $χ'' (q,ω)$ of the underdoped superconducting cuprate YBa_2 Cu_3 O_{6.5} ($T_c = 52 K$) over a wide range of energies and temperatures ($2 meV \leq \hbar ω\leq 120 meV$ and $5K \leq T \leq 200K$). Spin excitations of two different symmetries (even and odd under exchange of two adjacent CuO_2 layers) are observed which, surprisingly, are characterized by different temperature dependences. The excitations show dispersive behavior at high energies.

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Ph. Bourges, H. F. Fong, L. P. Regnault, J. Bossy, C. Vettier, D. L. Milius, I. A. Aksay, B. Keimer. 1997-10-03. High energy spin excitations in YBa_2 Cu_3 O_{6.5}. https://doi.org/10.1103/physrevb.56.r11439

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