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Nematic order in square lattice frustrated ferromagnets

Nic Shannon·Tsutomu Momoi·Philippe Sindzingre
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Abstract

We present a new scenario for the breakdown of ferromagnetic order in a two-dimensional quantum magnet with competing ferromagnetic and antiferromagnetic interactions. In this, dynamical effects lead to the formation of two-magnon bound states, which undergo Bose-Einstein condensation, giving rise to bond-centered nematic order. This scenario is explored in some detail for an extended Heisenberg model on a square lattice. In particular, we present numerical evidence confirming the existence of a state with d-wave nematic correlations but no long range magnetic order, lying between the saturated ferromagnetic and collinear antiferromagnetic phases of the ferromagnetic J1-J2 model. We argue by continuity of spectra that this phase is also present in a model with 4-spin cyclic exchange.

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Nic Shannon, Tsutomu Momoi, Philippe Sindzingre. 2005-12-15. Nematic order in square lattice frustrated ferromagnets. https://doi.org/10.1103/physrevlett.96.027213

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