Effects of frustration and cyclic exchange on the spin-1/2 Heisenberg antiferromagnet within the self-consistent spin-wave theory

Abstract

The relevance of the quasi-two-dimensional spin-1/2 frustrated quantum antiferromagnet due to its possibility of modelling the high-temperature superconducting parent compounds has resulted in numerous theoretical and experimental studies. This paper presents a detailed research of the influence of the varying exchange interactions on the model magnetic properties within the framework of self-consistent spin-wave theory based on Dyson-Maleev representation. Beside the nearest neighbour interaction within the plane, the planar frustration up to the third nearest neighbours, cyclic interaction and the interlayer coupling are taken into account. The detailed description of the elementary spin excitations, staggered magnetization, spin-wave velocity renormalization factor and groundstate energy is given. The results are compared to the predictions of the linear spin-wave theory and when possible also to the second-order perturbative spinwave expansion results. Finally, having at our disposal improved experimental results for the in-plane spin-wave dispersion in high-T c copper oxide La 2 CuO 4 , the self-consistent spin-wave theory is applied to that compound in order to correct earlier obtained set of exchange parameters and high temperature spin-wave dispersion. (Milica S. Rutonjski ) interaction, Quasi-two-dimensional antiferromagnetic copper oxides a c x y z J 2 J 3 J c J J Figure 1: (Color online) Magnetic unit cell (bold solid line) of 3D antiferromagnet with exchange interactions labeled. Two different orientations of spins are denoted by open and solid circles.

Thermodynamic properties of an S=12 ring-exchange model on the triangular lattice

“…The horizontal line at Ω(q)/J = 1 indicates the spin-wave excitation energy at M point in the purely triangular case with J c = J = 0. also reduced from ∼ 1.6J to ∼ 1.05J as J /J is increased. A similar dependence of the excitation energy on the interaction parameter J has been found also in the square lattice with the linear spin-wave theory [40].…”

“…These exchange interactions can be considered as an introduction of the charge fluctuation [16,17] and thus become more relevant for describing magnetic properties of Mott insulators in proximity of the metal-insulator transition [18][19][20][21][22][23][24][25][26][27]. While the ring-exchange interaction itself has long been considered for describing the magnetism in the three-dimensional solid 3 He [28][29][30][31][32][33][34], NiS 2 [35], and the parent compounds of high-T c cuprate superconductor such as La 2 CuO 4 [36][37][38][39][40][41], its importance in triangular-lattice systems near Mott transition is attracting a renewed attention recently [14,15,42,43] in organic Mott insulators κ-(ET) 2 Cu 2 (CN) 3 [44][45][46] and EtMe 3 Sb[Pd(dmit) 2 ] 2 [47,48], and a charge-density-wave Mott insulator 1T -TaS 2 [49,50].…”

Effects of frustration and Dzyaloshinskii-Moriya interaction on the spin-1/2 anisotropic Heisenberg antiferromagnet with the application to La2CuO4

“…The intention to thoroughly analyze the influence of the in-plane frustration on the magnetic properties of the system is * milica.rutonjski@df.uns.ac.rs corroborated by the fact that frustration is strongly pronounced in two-dimensional quantum magnets [17,18], though it is often not taken into account [5,6,8]. Our earlier results [19][20][21][22] also suggest that the model with the NNN interaction gives predictions in better agreement with the experimental data. Beside the aforementioned, the choice of the dominant interactions is supported by the fact that these interactions, especially NN, NNN and DM interaction, but also spin anisotropy to a lesser extent, show a distinctive pressure dependence [23,24], enabling one to affect the phase transition temperature by applying high pressures on the system.…”

Effects of Frustration and Dzyaloshinskii–Moriya Interaction on the Spin‐1/2 Anisotropic Heisenberg Antiferromagnet with the Application to La2CuO4

“…The intention to thoroughly analyze the influence of in‐plane frustration on the magnetic properties of the system is corroborated by the fact that frustration is strongly pronounced in 2D quantum magnets, [ 17,18 ] though it is often not taken into account. [ 5,6,8 ] Our earlier results [ 19–22 ] also suggest that the model with the NNN interaction gives predictions in better agreement with the experimental data. Besides the aforementioned, the choice of the dominant interactions is supported by the fact that these interactions, especially NN, NNN, and DM interaction, but also spin anisotropy to a lesser extent, show a distinctive pressure dependence, [ 23,24 ] enabling one to affect the phase transition temperature by applying high pressures on the system.…”