Spin gaps in coupled [ital t][ital J] ladders
Abstract
Spin gaps in coupled [ital t][ital J] ladders are investigated by exact diagonalization of small clusters up to 4[times]8 sites. At halffilling, the numerical results for the triplet excitation spectrum are in very good agreement with a secondorder perturbation expansion in terms of small interladder and intraladder exchange couplings between rungs ([ital J]/[ital J][prime][lt]0.25). The band of local triplet excitations moving coherently along the ladder (with momenta close to [pi]) is split by the interladder coupling. For intermediate couplings, finitesize scaling is used to estimate the spin gap. In the isotropic infinite fourchain system (two coupled ladders) we find a spin gap of 0.245[ital J], roughly half of the singleladder spin gap. When the system is hole doped, bonding and antibonding bound pairs of holes can propagate coherently along the chains and the spin gap remains finite.
 Authors:

 Laboratoire de Physique Quantique, Universite Paul Sabatier, 31062 Toulouse (France)
 Theoretische Physik, ETHHoenggerberg, 8093 Zuerich (Switzerland) and Interdisziplinaeres Projektzentrum fuer Supercomputing, ETHZentrum, 8092 Zuerich (Switzerland)
 Theoretische Physik, ETHHoenggerberg, 8093 Zuerich (Switzerland)
 Publication Date:
 OSTI Identifier:
 7071429
 Resource Type:
 Journal Article
 Journal Name:
 Physical Review, B: Condensed Matter; (United States)
 Additional Journal Information:
 Journal Volume: 50:9; Journal ID: ISSN 01631829
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTIFERROMAGNETIC MATERIALS; ELECTRON CORRELATION; HAMILTONIANS; HIGHTC SUPERCONDUCTORS; CHAINS; CRYSTAL DOPING; EXCHANGE INTERACTIONS; EXCITATION; HEISENBERG MODEL; HOLES; HUBBARD MODEL; SCALING LAWS; TRIPLETS; CORRELATIONS; CRYSTAL MODELS; ENERGYLEVEL TRANSITIONS; INTERACTIONS; MAGNETIC MATERIALS; MATERIALS; MATHEMATICAL MODELS; MATHEMATICAL OPERATORS; MULTIPLETS; QUANTUM OPERATORS; SUPERCONDUCTORS; 665411*  Basic Superconductivity Studies (1992)
Citation Formats
Poilblanc, D, Tsunetsugu, H, and Rice, T M. Spin gaps in coupled [ital t][ital J] ladders. United States: N. p., 1994.
Web. doi:10.1103/PhysRevB.50.6511.
Poilblanc, D, Tsunetsugu, H, & Rice, T M. Spin gaps in coupled [ital t][ital J] ladders. United States. https://doi.org/10.1103/PhysRevB.50.6511
Poilblanc, D, Tsunetsugu, H, and Rice, T M. Thu .
"Spin gaps in coupled [ital t][ital J] ladders". United States. https://doi.org/10.1103/PhysRevB.50.6511.
@article{osti_7071429,
title = {Spin gaps in coupled [ital t][ital J] ladders},
author = {Poilblanc, D and Tsunetsugu, H and Rice, T M},
abstractNote = {Spin gaps in coupled [ital t][ital J] ladders are investigated by exact diagonalization of small clusters up to 4[times]8 sites. At halffilling, the numerical results for the triplet excitation spectrum are in very good agreement with a secondorder perturbation expansion in terms of small interladder and intraladder exchange couplings between rungs ([ital J]/[ital J][prime][lt]0.25). The band of local triplet excitations moving coherently along the ladder (with momenta close to [pi]) is split by the interladder coupling. For intermediate couplings, finitesize scaling is used to estimate the spin gap. In the isotropic infinite fourchain system (two coupled ladders) we find a spin gap of 0.245[ital J], roughly half of the singleladder spin gap. When the system is hole doped, bonding and antibonding bound pairs of holes can propagate coherently along the chains and the spin gap remains finite.},
doi = {10.1103/PhysRevB.50.6511},
url = {https://www.osti.gov/biblio/7071429},
journal = {Physical Review, B: Condensed Matter; (United States)},
issn = {01631829},
number = ,
volume = 50:9,
place = {United States},
year = {1994},
month = {9}
}