2010/12/31 by P. E. Dargel, Piet E. Dargel, A. Honecker +5 · 41 citations
Mathematics · Physics and Astronomy · #Applied mathematics #Dimension (graph theory) #Eigenvalues and eigenvectors #Lanczos resampling #Mathematical analysis #Mathematics #Matrix (chemical analysis) #Physics #Physics of Superconductivity and Magnetism #Pure mathematics #Quantum and electron transport phenomena #Quantum many-body systems #Quantum mechanics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.83.161104
published in Physical Review B 83(16) (American Physical Society) · 4 pages, 4 figures, accepted at Phys. Rev. B (RC)
arxiv created 2011/04/13 · openalex publication_date 2011/04/22 · arxiv updated 2011/04/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Current widely used approaches to calculate spectral functions using the density-matrix renormalization group in frequency space either necessarily include an artificial broadening (correction-vector method), have limited resolution (time-domain density-matrix renormalization group with Fourier transform method), or are limited to low-energy properties or single dominant modes (original continued fraction method). Here we propose an adaptive Lanczos-vector method to calculate the coefficients of a continued fraction expansion of the spectral function iteratively. We show that one can obtain a very accurate representation of the spectral function very efficiently, and that one can also directly extract the spectral weights and poles for the discrete system.