152 citations · 442 across the 13 of their papers we have counts for
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Competing Gauge Fields and Entropically-Driven Spin Liquid to Spin Liquid Transition in non-Kramers Pyrochlores
Daniel Lozano-Gómez, Vincent Noculak, Jaan Oitmaa +4
Gauge theories are powerful tools in theoretical physics, allowing complex phenomena to be reduced to simple principles, and are used in both high-energy and condensed matter physi…
Spiral versus modulated collinear phases in the quantum ANNNH model
Jaan Oitmaa, Rajiv R. P. Singh
Motivated by the discovery of spiral and modulated collinear phases in several magnetic materials, we investigate the magnetic properties of Heisenberg spin S=1/2 antiferromagnets…
Are multiphase competition & order-by-disorder the keys to understanding Yb2Ti2O7?
L. D. C. Jaubert, Owen Benton, Jeffrey G. Rau +4
If magnetic frustration is most commonly known for undermining long-range order, as famously illustrated by spin liquids, the ability of matter to develop new collective mechanisms…
Magnons and Excitation Continuum in XXZ triangular antiferromagnetic model: Application to
E. A. Ghioldi, A. Mezio, L. O. Manuel +3
We investigate the excitation spectrum of the triangular-lattice antiferromagnetic model using series expansions and mean field Schwinger bosons approaches. The single-magnon…
Disorder Line and Incommensurate Floating Phases in the Quantum Ising Model on an Anisotropic Triangular Lattice
V. I. Iglovikov, R. T. Scalettar, J. Oitmaa +1
We present a Quantum Monte Carlo study of the Ising model in a transverse field on a square lattice with nearest-neighbor antiferromagnetic exchange interaction J and one diagonal…
Universal Finite Temperature Properties of a Three Dimensional Quantum Antiferromagnet in the Vicinity of a Quantum Critical Point
J. Oitmaa, Y. Kulik, O. P. Sushkov
We consider a 3-dimensional quantum antiferromagnet which can be driven through a quantum critical point (QCP) by varying a tuning parameter g. Starting from the magnetically order…
Spin-waves in the orthorombic square-lattice Heisenberg models: Application to the iron pnictide materials
R. Applegate, J. Oitmaa, R. R. P. Singh
Motivated by the observation of spatially anisotropic exchange constants in the iron pnictide materials, we study the spin-wave spectra of the Heisenberg mode…
Binding of a mobile hole by an impurity potential in the t-J model: parity breaking
O. P. Sushkov, J. Oitmaa
We revisit the problem of a single hole moving in the background of the two dimensional Heisenberg antiferromagnet. The hole is loosely bound by an impurity potential. We show that…
New quantum phase transitions in the two-dimensional J1-J2 model
O. P. Sushkov, J. Oitmaa, Zheng Weihong
We analyze the phase diagram of the frustrated Heisenberg antiferromagnet, the J1-J2 model, in two dimensions. Two quantum phase transitions in the model are already known: the sec…
Local impurities in 2D quantum antiferromagnets
V. N. Kotov, J. Oitmaa, O. Sushkov
The two-dimensional quantum Heisenberg antiferromagnet at zero temperature with two kinds of locally frustrating defects - isolated ferromagnetic bonds and impurity spins, is studi…
Local magnetic impurities in the 2D quantum Heisenberg antiferromagnet
V. N. Kotov, J. Oitmaa, O. Sushkov
We consider the two-dimensional (2D) quantum Heisenberg antiferromagnet at zero temperature with two types of locally frustrating perturbations - an isolated ferromagnetic bond (FM…