Spinon deconfinement in doped frustrated quantum antiferromagnets

TL;DR

This paper investigates how doping affects spinon confinement in frustrated quantum antiferromagnets, revealing intermediate behaviors and extended bound states that connect experimental observations and suggest a nearby deconfined critical point.

Contribution

It demonstrates the existence of intermediate confinement regimes and extended spinon-holon bound states in doped frustrated antiferromagnets, linking theory with experimental signatures.

Findings

Intermediate confinement behavior identified in the J1-J2-J3 model.

Extended spinon-holon bound states observed for mobile holes.

Evidence suggests a nearby deconfined critical point.

Abstract

The confinement of a spinon liberated by doping two-dimensional frustrated quantum antiferromagnets with a non-magnetic impurity or a mobile hole is investigated. For a static vacancy, an intermediate behavior between complete deconfinement (kagome) and strong confinement (checkerboard) is identified in the J_1{-}J_2{-}J_3 model on the square lattice, with the emergence of two length scales, a spinon confinement length larger than the magnetic correlation length. For mobile holes, this translates into an extended spinon-holon boundstate allowing one to bridge momentum (ARPES spectral function) and real space (STM) experimental observations. These features provide clear evidence for a nearby "deconfined critical point" in a doped microscopic model.