IFIR   05409
INSTITUTO DE FISICA DE ROSARIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Magnons vs free spinons in finite quantum frustrated antiferromagnets
Autor/es:
I. J. HAMAD; L. O. MANUEL; A. E. TRUMPER
Lugar:
Centro Atómico Constituyentes, Buenos Aires
Reunión:
Workshop; At the Frontiers of Condensed Matter IV; 2008
Institución organizadora:
Comisión Nacional de Energía Atómica
Resumen:
We have investigated the validity of vacancy doping of a finite J1− J3 frustrated Heisenberg model as a test of the possible existence of fractional spin excitations. Using a generalized t−J1−J3 model we have computed the vacancy spectral functions in the self consistent Born approximation.We have found that by including spiral fluctuations in the magnetic ground state, the spectral functions on finite systems agree very well with the unbiased exact ones. In contrast to the recent proposal that the quasiparticle weight reduction could be a signal of a spinon free excitation in finite systems, we have found strong evidence that such a reduction isdue to the existence of spiral fluctuations.