207 citations · 2.6k across the 59 of their papers we have counts for
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Phase Diagram of the BCC S=1/2 Heisenberg Antiferromagnet with First and Second Neighbor Exchange
Jaan Oitmaa, Weihong Zheng
We use linked-cluster series expansions, both at T=0 and high temperature, to analyse the phase structure of the spin-$\half$ Heisenberg antiferromagnet with competing first and se…
Criticality in coupled quantum spin-chains with competing ladder-like and two-dimensional couplings
Pinaki Sengupta, Weihong Zheng, Rajiv R. P. Singh
Motivated by the geometry of spins in the material CaCuO, we study a two-layer, spin-half Heisenberg model, with nearest-neighbor exchange couplings J and α*J along the two…
Dynamical Structure Factor for the Alternating Heisenberg Chain: A Linked Cluster Calculation
Chris J. Hamer, Weihong Zheng, Rajiv R. P. Singh
We develop a linked cluster method to calculate the spectral weights of many-particle excitations at zero temperature. The dynamical structure factor is expressed as a sum of exclu…
An Application of Feynman-Kleinert Approximants to the Massive Schwinger Model on a Lattice
T. M. R. Byrnes, C. J. Hamer, Zheng Weihong +1
A trial application of the method of Feynman-Kleinert approximants is made to perturbation series arising in connection with the lattice Schwinger model. In extrapolating the latti…
A closer look at symmetry breaking in the collinear phase of the Heisenberg Model
R. R. P. Singh, W. Zheng, J. Oitmaa +2
The large limit of the square-lattice Heisenberg antiferromagnet is a classic example of order by disorder where quantum fluctuations select a collinear ground stat…
The Mixed Spin S=(1/2,1) XXZ Ferrimagnet at Zero Temperature
Weihong Zheng, J. Oitmaa
Linked cluster series expansions about the Ising limit are used to study ground state preperties, viz. ground state energy, magnetization and excitation spectra, for mixed spin S=(…