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Novel neutron resonance mode in $d_{x^2-y^2}$ superconductors

Ilya Eremin·Dirk K. Morr·Andrey V. Chubukov·Karl Bennemann·Michael R. Norman
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Abstract

We show that a new resonant magnetic excitation at incommensurate momenta, observed recently by inelastic neutron scattering experiments on YBa$_2$Cu$_3$O$_{6.85}$ and YBa$_2$Cu$_3$O$_{6.6}$, is a {\it spin exciton}. Its location in the magnetic Brillouin zone and its frequency are determined by the momentum dependence of the particle-hole continuum. We identify several features that distinguish this novel mode from the previous resonance mode observed near ${\bf Q}=(π,π)$, such as its intensity maximum which occurs in a different part of the magnetic Brillouin zone.

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Ilya Eremin, Dirk K. Morr, Andrey V. Chubukov, Karl Bennemann, Michael R. Norman. 2004-09-22. Novel neutron resonance mode in $d_{x^2-y^2}$ superconductors. https://doi.org/10.1103/physrevlett.94.147001

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