33 citations · 72 across the 5 of their papers we have counts for
5 papers
Electronic correlations in the Hubbard model on a bi-partite lattice
Wissam A. Ameen, Niels R. Walet, Yang Xian
In this work we study the Hubbard model on a bi-partite lattice using the coupled-cluster method (CCM). We first investigate what, within this approach, allows us to reproduce the…
Longitudinal excitations in triangular lattice antiferromagnets
Mohammad Merdan, Y. Xian
We study the longitudinal excitations of quantum antiferromagnets on a triangular lattice by a recently proposed microscopic many-body approach based on magnon-density waves. We ca…
An extension of the coupled-cluster method: A variational formalism
Y. Xian
A general quantum many-body theory in configuration space is developed by extending the traditional coupled cluter method (CCM) to a variational formalism. Two independent sets of…
A microscopic approach to the dimerization in the frustrated spin-1/2 antiferromagnetic chains
Yang Xian
The spontaneous dimerization of the frustrated spin- antiferromagnetic chains is studied by a microscopic approach based on a proper set of composite operators (i.e., pseu…
Exact Results of Dimerization Order Parameter in Antiferromagnetic Chains
Y. Xian
After a proper definition of the dimerization order parameter for a spin- system, I show that this order parameter in the () antiferromagnetic chains (or equival…