Critical exponents of random XX and XY chains: Exact results via random walks

H. Rieger, R. Juhász, F. Iglói

Research output: Contribution to journalArticle

6 Citations (Scopus)


We study random XY and (dimerized) XX spin-1/2 quantum spin chains at their quantum phase transition driven by the anisotropy and dimerization, respectively. Using exact expressions for magnetization, correlation functions and energy gap, obtained by the free fermion technique, the critical and off-critical (Griffiths-McCoy) singularities are related to persistence properties of random walks. In this way we determine exactly the decay exponents for surface and bulk transverse and longitudinal correlations, correlation length exponent and dynamical exponent.

Original languageEnglish
Pages (from-to)409-412
Number of pages4
JournalEuropean Physical Journal B
Issue number3
Publication statusPublished - Feb 1 2000



  • 71.55.Jv Disordered structures; amorphous and glassy solids
  • 75.10.Jm Quantized spin models
  • 75.50.Lk Spin glasses and other random magnets

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

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