Fermionic versus bosonic descriptions of one-dimensional spin-gapped antiferromagnets

• Veröffentlicht in: Физика низких температур
• Datum: 2005
• Hauptverfasser: Yamamoto, Shoji, Funase, Kei-ichi
• Format: Artikel
• Sprache: Englisch
• Veröffentlicht: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2005
• Schlagworte: К семидесятилетию антиферромагнетизма
• Online Zugang: https://nasplib.isofts.kiev.ua/handle/123456789/121692
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Zitieren: Fermionic versus bosonic descriptions
 of one-dimensional spin-gapped antiferromagnets / Shoji Yamamoto, Kei-ichi Funase // Физика низких температур. — 2005. — Т. 31, № 8-9. — С. 974-983. — Бібліогр.: 112 назв. — англ.

In terms of spinless fermions and spin waves, we describe magnetic properties of a spin-1/2 ferromagnetic–
 antiferromagnetic bond-alternating chain which behaves as a Haldane-gap antiferromagnet.
 On one hand, we employ the Jordan–Wigner transformation and treat the fermionic
 Hamiltonian within the Hartree–Fock approximation. On the other hand, we employ the Holstein–
 Primakoff transformation and modify the conventional spin-wave theory so as to restore the
 sublattice symmetry. We calculate the excitation gap, the specific heat, the magnetic susceptibility,
 magnetization curves, and the nuclear spin-lattice relaxation rate with varying bond alternation.
 These schemes are further applied to a bond-alternating tetramerized chain which behaves as
 a ferrimagnet. The fermionic language is particularly stressed as a useful tool to investigate one-dimensional
 spin-gapped antiferromagnets, while the bosonic one works better for ferrimagnets.