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Is the pi-particle responsible for the 41 meV peak in YBa_2Cu_3O_7?

Martin Greiter
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Abstract

It is argued that there is no low-energy resonance associated with the pi-operators introduced by Demler and Zhang. This implies that the Hubbard model does not possess an approximate SO(5) symmetry generated by these operators. Recent finite-size studies are re-interpreted accordingly.

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Martin Greiter. 1997-05-06. Is the pi-particle responsible for the 41 meV peak in YBa_2Cu_3O_7?. https://doi.org/10.1103/physrevlett.79.4898

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