We present a new approach to determine an accurate variational wave function for general quantum spin models, completely defined by a consistency requirement with the simple and well-known linear spin-wave expansion. With this wave function, it is also possible to obtain the correct behavior of the long distance correlation functions for the 1D S=1/2 antiferromagnet. In 2D the proposed spin-wave wave function represents an excellent approximation to the exact ground state of the S=1/2 XY model. We obtained accurate values for the correlation functions and discuss their physical relevance.
Spin-wave wave function for quantum spin models / Franjic, F; Sorella, Sandro. - In: PROGRESS OF THEORETICAL PHYSICS. - ISSN 0033-068X. - 97:3(1997), pp. 399-406. [10.1143/PTP.97.399]
Spin-wave wave function for quantum spin models
Sorella, Sandro
1997-01-01
Abstract
We present a new approach to determine an accurate variational wave function for general quantum spin models, completely defined by a consistency requirement with the simple and well-known linear spin-wave expansion. With this wave function, it is also possible to obtain the correct behavior of the long distance correlation functions for the 1D S=1/2 antiferromagnet. In 2D the proposed spin-wave wave function represents an excellent approximation to the exact ground state of the S=1/2 XY model. We obtained accurate values for the correlation functions and discuss their physical relevance.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
