The low energy photoemission spectra in quantum antiferromagnets are studied by using several approximation-free calculations and rigorous theorems. The important and measurable property found is that the hole eigenstates with momenta differing by the antiferromagnetic wave vector Q are equivalent and degenerate in energy. However, the corresponding eigenstates differ by the presence or the absence of a well-defined quasiparticle corresponding to a singular. zero-energy, magnon, carrying spin one and momentum Q. This difference between the two eigenstates affects dramatically the spectral weight as a function of the scattered momentum, since a sharp effect at the surface of the magnetic Brillouin zone is predicted, in apparent agreement with recent experimental data.
Sharp photoemission spectra in the quantum antiferromagnet / Sorella, Sandro. - In: PHYSICAL REVIEW. B, CONDENSED MATTER. - ISSN 0163-1829. - 53:22(1996), pp. 15119-15128. [10.1103/PhysRevB.53.15119]
Sharp photoemission spectra in the quantum antiferromagnet
Sorella, Sandro
1996-01-01
Abstract
The low energy photoemission spectra in quantum antiferromagnets are studied by using several approximation-free calculations and rigorous theorems. The important and measurable property found is that the hole eigenstates with momenta differing by the antiferromagnetic wave vector Q are equivalent and degenerate in energy. However, the corresponding eigenstates differ by the presence or the absence of a well-defined quasiparticle corresponding to a singular. zero-energy, magnon, carrying spin one and momentum Q. This difference between the two eigenstates affects dramatically the spectral weight as a function of the scattered momentum, since a sharp effect at the surface of the magnetic Brillouin zone is predicted, in apparent agreement with recent experimental data.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.