arXiv:2305.18124 · Journal of Physics Condensed Matter

Magnetic properties of delta- and kagome-like chains with competing interactions

Д. В. Дмитриев, V. Ya. Krivnov

Published Jul 21, 2023• 3 citations

Abstract

Abstract We study the delta-chain with spin-1 on basal sites and spin- 1 2 on apical sites. The Heisenberg interaction between neighbor basal spins is antiferromagnetic (AF) and the interaction between basal and apical spins is ferromagnetic (F). We show that the magnetization curve of this model is the same as that of the spin- 1 2 kagome-like chain with competing Heisenberg interactions. The ground state phase diagram of the latter as a function of the ratio between the AF and F interaction, α, consists of the ferromagnetic, ferrimagnetic and singlet phases. We study the magnetic properties in each ground state phase and analyze the magnetization curves. We show that there are magnetization plateaus and jumps in definite regions of value α. We compare the magnetic properties of considered models with those of the spin- 1 2 delta chain.

DOI: 10.1088/1361-648x/ace9a9

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arXiv:2305.18124 · Journal of Physics Condensed Matter

Magnetic properties of delta- and kagome-like chains with competing interactions

Д. В. Дмитриев, V. Ya. Krivnov

Published Jul 21, 2023• 3 citations

arXiv HTML PDF

Abstract

DOI: 10.1088/1361-648x/ace9a9

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By means of the density matrix renormalization group (DMRG) method, the magnetic properties of the J-J-J

^{\prime}

quantum Heisenberg chains with spin

S=1/2

, 1, 3/2 and 2 in the ground states are investigated in the presence of a magnetic field. Two different cases are considered: (a) when

J

is antiferromagnetic and

J^{\prime}

is ferromagnetic (i.e. the AF-AF-F chain), the system is a ferrimagnet. The plateaus of the magnetization are observed. It is found that the width of the plateaus decreases with increasing the ferromagnetic coupling, and disappears when

% J^{\prime}/J

passes over a critical value. The saturated field is observed to be independent of the ferromagnetic coupling; (b) when

J

is ferromagnetic and

J^{\prime}

is antiferromagnetic (i.e. the F-F-AF chain), the system becomes an antiferromagnet. The plateaus of the magnetization are also seen. The width of the plateaus decreases with decreasing the antiferromagnetic coupling, and disappears when $J^{\prime}/J $ passes over a critical value. Though the ground state properties are quite different, the magnetization plateaus in both cases tend to disappear when the ferromagnetic coupling becomes more dominant. Besides, no fundamental difference between the systems with spin half-integer and integer has been found.