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arXiv · 1602.02979

Quantum Monte Carlo Study of Long-Range Transverse-Field Ising Models on the Triangular Lattice

Stephan Humeniuk
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Abstract

Motivated by recent experiments with a Penning ion trap quantum simulator, we perform numerically exact Stochastic Series Expansion quantum Monte Carlo simulations of long-range transverse-field Ising models on a triangular lattice for different decay powers $\alpha$ of the interactions. The phase boundary for the ferromagnet is obtained as a function of $\alpha$. For antiferromagnetic interactions, there is strong indication that the transverse field stabilizes a clock ordered phase with sublattice magnetization $(M,-\frac{M}{2}, -\frac{M}{2})$ with unsaturated $M < 1$ in a process known as "order by disorder" similar to the nearest neighbour antiferromagnet on the triangular lattice. Connecting the known limiting cases of nearest neighbour and infinite-range interactions, a semiquantitative phase diagram is obtained. Magnetization curves for the ferromagnet for experimentally relevant system sizes and with open boundary conditions are presented.

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BibTeXRIS

Stephan Humeniuk. 2016-02-09. Quantum Monte Carlo Study of Long-Range Transverse-Field Ising Models on the Triangular Lattice. https://doi.org/10.1103/physrevb.93.104412

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