Susceptibility and excitation spectrum of (VO)[sub 2]P[sub 2]O[sub 7] in ladder and dimer-chain models

Journal Article · Thu Sep 01 04:00:00 EDT 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.50.6817· OSTI ID:6971946

Barnes, T ^[1]; Riera, J ^[2]

---

1. Physics Division and Center for Computationally Intensive Physics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States) Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States)
2. Physics Division and Center for Computationally Intensive Physics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States) Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)

We present numerical results for the magnetic susceptibility of a Heisenberg antiferromagnetic spin ladder as a function of temperature and the spin-spin interaction strengths [ital J][sub [perpendicular]] and [ital J][sub [parallel]]. These are contrasted with bulk-limit results for the dimer chain. A fit to the experimental susceptibility of the candidate spin-ladder compound vanadyl pyrophosphate, (VO)[sub 2]P[sub 2]O[sub 7], gives the parameters [ital J][sub [perpendicular]]=7.82 meV and [ital J][sub [parallel]]=7.76 meV. With these values we predict a singlet-triplet energy gap of [ital E][sub gap]=3.9 meV, and give a numerical estimate of the ladder triplet dispersion relation [omega]([ital k]). In contrast, a fit to the dimer-chain model leads to [ital J][sub 1]=11.11 meV and [ital J][sub 2]=8.02 meV, which predicts a gap of [ital E][sub gap]=4.9 meV.

• DOE Contract Number: AC05-84OR21400; FG05-87ER40376
• OSTI ID: 6971946
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 50:10; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665000* -- Physics of Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOY SYSTEMS
ANTIFERROMAGNETISM
CHALCOGENIDES
CRYSTAL MODELS
DIMERS
ENERGY GAP
ENERGY SPECTRA
HEISENBERG MODEL
MAGNETIC PROPERTIES
MAGNETIC SUSCEPTIBILITY
MAGNETISM
MATHEMATICAL MODELS
NUMERICAL SOLUTION
OXIDES
OXYGEN COMPOUNDS
PHOSPHORUS COMPOUNDS
PHOSPHORUS OXIDES
PHYSICAL PROPERTIES
SPECTRA
TEMPERATURE DEPENDENCE
TERNARY ALLOY SYSTEMS
TRANSITION ELEMENT COMPOUNDS
VANADIUM COMPOUNDS
VANADIUM OXIDES