Dy-V magnetic interaction and local structure bias on the complex spin and orbital ordering in Dy1−xTbxVO

Abstract

The spin and orbital ordering in Dy1−xTbxVO3 (x = 0 and 0.2) was studied by measuring x-ray powder diffraction, magnetization, specific heat, and neutron single crystal diffraction. The results show that G-OO/C-AF and C-OO/G-AF phases coexist in Dy0.8Tb0.20VO3 in the temperature range 2 K∼60 K and the volume fraction of each phase is temperature and field dependent. The ordering of Dy moments at T* = 12 K induces a transition from G-OO/C-AF to a C-OO/G-AF phase. Magnetic fields suppress the long range order of Dy moments and thus the C-OO/G-AF phase below T*. The polarized moments induced at the Dy sublattice by external magnetic fields couple to the V 3d moments and this coupling favors the G-OO/C-AF state. Also discussed is the effect of the Dy-V magnetic interaction and local structure distortion on the spin and orbital ordering in Dy1−xTbxVO3.

Observation of large refrigerant capacity in the HoVO3 vanadate single crystal

“…25 It is worth noting that the RVO 3 vanadates reveal a weak specific heat at low temperatures (around 10 K). [26][27][28] Consequently, a large adiabatic temperature change is expected in HoVO 3 . According to Refs.…”

Raman and infrared study of 4f electron–phonon coupling in HoVO3

“…Rare earth magnetostrictive effects can play a similar role and favor a specific V 3+ orbital and spin order. Hence, dramatic effects were observed in DyVO 3 where the 4f magnetic moments ordering partially restores the C-OO configuration in the G-OO phase [11]. Inversely, the VO 3 matrix interaction with the Ho 3+ spin explains the unusually high polarization of the Ho 3+ spins above T * and the Ho 3+ spin polarization anomaly at T N2 [7,18].…”

“…Particularly, the RVO 3 vanadates, characterized by two distinct orbital ordered states have recently attracted an increasing interest due to their fascinating physical properties [5][6][7]. In these systems, the orbital-active t 2g electrons are very sensitive to the ionic radius R 3+ , the temperature and the external stimuli [8][9][10][11]. One of the orbital ordered states is driven by the superexchange interaction leading to strong orbital fluctuations [8,9,[12][13][14].…”