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arXiv · 1706.07909

Frustrated honeycomb-lattice bilayer quantum antiferromagnet in a magnetic field

Taras Krokhmalskii·Vasyl Baliha·Oleg Derzhko·Jörg Schulenburg·Johannes Richter
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Abstract

Frustrated bilayer quantum magnets have attracted attention as flat-band spin systems with unconventional thermodynamic properties. We study the low-temperature properties of a frustrated honeycomb-lattice bilayer spin-$\frac{1}{2}$ isotropic ($XXX$) Heisenberg antiferromagnet in a magnetic field by means of an effective low-energy theory using exact diagonalizations and quantum Monte Carlo simulations. Our main focus is on the magnetization curve and the temperature dependence of the specific heat indicating a finite-temperature phase transition in high magnetic fields.

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Taras Krokhmalskii, Vasyl Baliha, Oleg Derzhko, Jörg Schulenburg, Johannes Richter. 2017-06-24. Frustrated honeycomb-lattice bilayer quantum antiferromagnet in a magnetic field. https://doi.org/10.1016/j.physb.2017.09.064

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