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arXiv · 2412.17911

Exotic phase transitions in spin ladders with discrete symmetries that emulate spin-1/2 bosons in two dimensions

Bo Han·David F. Mross
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Abstract

We introduce a spin ladder with discrete symmetries designed to emulate a two-dimensional spin-1/2 boson system at half-filling. Using global properties, such as the structure of topological defects, we establish a correspondence between the two systems and construct a dictionary of symmetries and operators. In particular, translation invariance leads to Lieb-Schultz-Mattis constraints for both systems, resulting in exotic deconfined quantum critical points. Subsequently, we study the spin ladder in detail. An exact duality transformation maps it onto a $\mathbb{Z}_2$ gauge theory of three partons, analogous to the U(1) gauge theory of chargons and spinons in two-dimensional spin-1/2 boson systems. With the mapping between spins and partons, we construct exactly solvable models for all pertinent symmetry-breaking phases and analyze their transitions. We further make connections between our exact analysis and conventional parton gauge theories.

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Bo Han, David F. Mross. 2024-12-23. Exotic phase transitions in spin ladders with discrete symmetries that emulate spin-1/2 bosons in two dimensions. https://arxiv.org/abs/2412.17911

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