1997/11/25 by P. Henelius, S. M. Girvin · 2 citations
Mathematics · Physics and Astronomy · #Chain (unit) #Combinatorics #Computer science #Crossover #Fermion #Machine learning #Mathematical physics #Mathematics #Phase (matter) #Physics #Physics of Superconductivity and Magnetism #Quantum many-body systems #Quantum mechanics #Randomness #Renormalization group #Singlet state #Spin (aerodynamics) #Statistical physics #Statistics #Theoretical and Computational Physics #Thermodynamics #cond-mat.dis-nn
paper · pdf · doi:10.1103/physrevb.57.11457
11 pages, 19 figures
arxiv created 1997/11/25 · openalex publication_date 1998/05/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The effects of randomness and dimerization on the spin-1/2 XX chain are studied by a mapping to free fermions. Results are presented for the transverse and longitudinal components of the average and typical spin- and string-correlation functions. Contrary to previous numerical evidence, the decay exponents of all the above correlation functions are found to be in good agreement with the theoretical renormalization-group predictions for the random singlet phase. We also present crossover functions for the above correlation functions in the random dimer phase. Disorder averages have been taken for system sizes up to N=1024, about ten times larger than in previous studies.