Magnetic short-range order and spin freezing in the quasi-2D system LuFeMgO4

Quasi-two-dimensional spin correlations in the triangular lattice bilayer spin glass LuCoGaO4

“…within the plane of the bilayers that is clearly observed to be peaked at wave vectors Q = (1/3, 1/3, L). This type of scattering has similarly been observed in several samples of other members of the YbFe 2 O 4 family, 13,16 principally as a broad peak centered at Q ∼ 1.27 A −1 . Such a feature is typical for antiferromagnetically interacting moments in a triangular geometry and suggests a √ 3 × √ 3 local magnetic structure.…”

“…26 The dilute case has been most extensively investigated for LuFeMgO 4 . [16][17][18]20,21,27 LuCuGaO 4 has recently been shown to display spin liquid behavior with a gapless spin excitation spectrum down to 50 mK, 28 in contrast to expectations of spin glass behavior based on earlier susceptibility measurements. 12 The effects of spin anisotropy on the phase transitions have been investigated and compared for YbCoGaO 4 and LuCoGaO 4 by Radelytskyi et al.…”

“…This observation is similar to the result reported for powder samples of LuFeMgO 4 , for which the short-range magnetic correlations observed as diffuse scattering intensity at |Q| ∼ 1.25Å −1 have been described within the above model by including correlations up to the 12th neighbor shell, indicating a somewhat larger correlation length in this compound. 16 In the case of LuCuGaO 4 , in which broad and extremely weak magnetic diffuse scat- Fits to Eqn. 1 show good agreement with short-range, twodimensional magnetic correlations extending beyond the 5th nearest neighbor shell at ∼ 6Å.…”

“…In addition to LuCoGaO 4 , LuCuGaO 4 , LuM FeO 4 (M =Zn, Fe, Co, Cu), YbM FeO 4 (M =Mg, Fe, Co, Cu), YbCuGaO 4 , YbCoGaO 4 as well as YbMgGaO 4 have been studied. 9,[12][13][14][15][16][17][18][19][20][21][22][23] In the series based on the nonmagnetic Lu as R atom, the multiferroic LuFe 2 O 4 has attracted particular interest due to the observed interplay of cation and magnetic ordering. This material exhibits two-or three-dimensional ferrimagnetic ordering below ∼240 K depending on oxygen stoichiometry, 24,25 and a chargeordered state below ∼320 K which is thought to underlie the ferroelectricity.…”

Nanometer-Sized Domain Structures in LuFeMO4(M= Cu, Co) Revealed by Energy-Filtered Transmission Electron Microscopy

“…For instance, LuFeCoO 4 and LuFeMgO 4 show magnetic transitions at 75 K and 33 K, respectively [7][8][9]. In addition, there exist the magnetic ordered structure with the short-ranged coherence, which Downloaded by [The University of Manchester Library] at 08:23 14 October 2014 is characterized by the magnetic superlattice structure with the wave vector q = [1/3 1/3 l] [10,11]. Neutron diffraction experiments and Monte Carlo simulation revealed that the presence of a local cationic ordering of Fe 3+ and Mg 2+ in LuFeMgO 4 [8].…”