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  • Open Access

Emergent Spacetime Supersymmetry at 2D Fractionalized Quantum Criticality

Zhengzhi Wu1,2,*, Zhou-Quan Wan3,*, Shao-Kai Jian4,†, and Hong Yao1,‡

  • *These authors contributed equally to this work.
  • †Contact author: sjian@tulane.edu
  • ‡Contact author: yaohong@tsinghua.edu.cn
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Phys. Rev. Lett. 136, 256502 – Published 24 June, 2026

DOI: https://doi.org/10.1103/zqnh-tb1d

Abstract

While experimental evidence for spacetime supersymmetry (SUSY) in particle physics remains elusive, condensed matter systems offer a promising arena for its emergence at quantum critical points (QCPs). Although there have been a variety of proposals for emergent SUSY at symmetry-breaking QCPs, the emergence of SUSY at fractionalized QCPs remains largely unexplored. Here, we demonstrate emergent spacetime SUSY at a fractionalized QCP in the Kitaev honeycomb model with Su-Schrieffer-Heeger (SSH) spin-phonon coupling. Specifically, through numerical computations and analytical analysis, we show that the anisotropic SSH-Kitaev model hosts a fractionalized QCP between a Dirac spin liquid and an incommensurate or commensurate valence-bond-solid phase coexisting with Z2 topological order. A low-energy field theory incorporating phonon quantum fluctuations reveals that this fractionalized QCP features an emergent N=2 spacetime SUSY. We further discuss their universal experimental signatures in thermal transport and viscosity, highlighting the concrete lattice realization of emergent SUSY at a fractionalized QCP in 2D.

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Phys. Rev. Lett. 136, 256502– Published 24 June, 2026
  • Received 21 October 2025
  • Revised 27 February 2026
  • Accepted 20 April 2026
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