Dynamical spin response functions for Heisenberg ladders

Journal Article · Fri May 01 04:00:00 EDT 1998 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.57.10603· OSTI ID:601007

Yang, D B ^[1]; Haxton, W C ^[2]

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1. Department of Physics, Harvard University, Cambridge, Massachusetts02138
2. Institute for Nuclear Theory, Box 351550, and Department of Physics, Box 351560, University of Washington, Seattle, Washington 98195 (United States)

We present the results of a numerical study of the 2 {times}L spin- (1) /(2) Heisenberg ladder. Ground state energies and the singlet-triplet energy gaps for 4{le}L{le}14 and J{sub {perpendicular}}/J{sub {vert_bar}{vert_bar}} = 1 were obtained in a Lanczos calculation and checked against earlier calculations by Barnes {ital et al.} (even L{le} 12). A related moments technique is then employed to evaluate spin response functions for L = 12 and a range of J{sub {perpendicular}}/J{sub {vert_bar}{vert_bar}} (0 {endash} 5). We comment on two issues, the need for reorthogonalization and the rate of convergence, that affect the numerical utility of the moments treatment of response functions. {copyright} {ital 1998} {ital The American Physical Society}

• OSTI ID: 601007
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 17 Vol. 57; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ENERGY GAP
GROUND STATES
HEISENBERG MODEL
RESPONSE FUNCTIONS
SPIN