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arXiv · 1909.01594

Bose-Einstein condensation of deconfined spinons in two dimensions

Adam Iaizzi·Harley D Scammell·Oleg P Sushkov·Anders W Sandvik
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Abstract

The transition between the N\'{e}el antiferromagnet and the valence-bond solid state in two dimensions has become a paradigmatic example of deconfined quantum criticality, a non-Landau transition characterized by fractionalized excitations (spinons). We consider an extension of this scenario whereby the deconfined spinons are subject to a magnetic field. The primary purpose is to identify the exotic scenario of a Bose-Einstein condensate of spinons. We employ quantum Monte Carlo simulations of the \mbox{$J$-$Q$} model with a magnetic field and perform a quantum field theoretic analysis of the magnetic field and temperature dependence of thermodynamic quantities. The combined analysis provides compelling evidence for the Bose-Einstein condensation of spinons and also demonstrates an extended temperature regime in which the system is best described as a gas of spinons interacting with an emergent gauge field.

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Adam Iaizzi, Harley D Scammell, Oleg P Sushkov, Anders W Sandvik. 2019-09-04. Bose-Einstein condensation of deconfined spinons in two dimensions. https://doi.org/10.1103/physrevb.101.104412

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