177 citations · 470 across the 10 of their papers we have counts for
10 papers
Spin- Kitaev-Heisenberg model on the honeycomb lattice: A high-order treatment via the many-body coupled cluster method
Marios Georgiou, Ioannis Rousochatzakis, Damian J. J. Farnell +2
We study the spin- Kitaev-Heisenberg model on the honeycomb lattice for , and , by using the coupled cluster method (CCM) of microscopic quantum many-body th…
Ground-State Ordering of the -- Model on the Simple Cubic and Body-Centered Cubic Lattices
D. J. J. Farnell, O. Götze, J. Richter
The -- Heisenberg model is a "canonical" model in the field of quantum magnetism in order to study the interplay between frustration and quantum fluctuations as well as q…
Quantum s = 1/2 Antiferromagnets on Archimedean Lattices: The Route from Semiclassical Magnetic Order to Nonmagnetic Quantum States
D. J. J. Farnell, O. Goetze, J. Richter +2
We investigate ground states of =1/2 Heisenberg antiferromagnets on the eleven two-dimensional (2D) Archimedian lattices by using the coupled cluster method. Magnetic interactio…
The spin-half Heisenberg antiferromagnet on two Archimedian lattices: From the bounce lattice to the maple-leaf lattice and beyond
D. J. J. Farnell, R. Darradi, R. Schmidt +1
We investigate the ground state of the two-dimensional Heisenberg antiferromagnet on two Archimedean lattices, namely, the maple-leaf and bounce lattices as well as a generalized $…
The frustrated spin-1/2 J1-J2 Heisenberg ferromagnet on the square lattice: Exact diagonalization and Coupled-Cluster study
J. Richter, R. Darradi, J. Schulenburg +2
We investigate the ground-state magnetic order of the spin-1/2 J1-J2 Heisenberg model on the square lattice with ferromagnetic nearest-neighbor exchange J1<0 and frustrating antife…
High-Order Coupled Cluster Method (CCM) Formalism 2 -- "Generalised" Expectation Values: Spin-Spin Correlation Functions for Frustrated and Unfrustrated 2D Antiferromagnets
D. J. J. Farnell
Recent developments of high-order CCM have been to extend existing formalism and codes to for both the ground and excited states. In this article, we describe how…
Direct calculation of the spin stiffness on square, triangular and cubic lattices using the coupled cluster method
S. E. Krüger, R. Darradi, J. Richter +1
We present a method for the direct calculation of the spin stiffness by means of the coupled cluster method. For the spin-half Heisenberg antiferromagnet on the square, the triangu…
Ab Initio Calculations of the Spin-Half XY Model
D. J. J. Farnell, M. L. Ristig
In this article, the correlated basis-function (CBF) method is applied for the first time to the quantum spin-half {\it XY} model on the linear chain, the square lattice, and the s…
Coupled Cluster Treatment of the XY model
D. J. J. Farnell, S. E. Krueger, J. B. Parkinson
We study quantum spin systems in the 1D, 2D square and 3D cubic lattices with nearest-neighbour XY exchange. We use the coupled-cluster method (CCM) to calculate the ground-state e…
Numerical and approximate analytical results for the frustrated spin-1/2 quantum spin chain
R. J. Bursill, G. A. Gehring, D. J. J. Farnell +3
We study the frustrated phase of the quantum spin- system with nearest-neighbour and next-nearest-neighbour isotropic exchange known as the Majumdar-Ghosh Hami…