TY - JOUR
T1 - Magnetization reversal driven by electron localization-delocalization crossover in the inverse spinel Co2VO4
AU - Kademane, Abhijit Bhat
AU - Bhandari, Churna
AU - Paudyal, Durga
AU - Cottrell, Stephen
AU - Das, Pinaki
AU - Liu, Yong
AU - Yiu, Yuen
AU - Kumar, C. M. Naveen
AU - Siemensmeyer, Konrad
AU - Hoser, Andreas
AU - Quintero-Castro, Diana Lucia
AU - Vaknin, David
AU - Toft-Petersen, Rasmus
PY - 2022
Y1 - 2022
N2 - Neutron diffraction, magnetization, and muon spin relaxation measurements, supplemented by density functional theory (DFT) calculations are employed to unravel temperature-driven magnetization reversal in inverse spinel Co2VO4. All measurements show a second-order magnetic phase transition at TC=168K to a collinear ferrimagnetic phase. Neutron diffraction measurements reveal two antiparallel ferromagnetic (FM) sublattices, belonging to magnetic ions on two distinct crystal lattice sites, where the relative balance between the two sublattices determine the net FM moment in the unit cell. As the evolution of the ordered moment with temperature differs between the two sublattices, the net magnetic moment reaches a maximum at TNC=138K and reverses its sign at TMR=65K. The DFT results suggest that the underlying microscopic mechanism for the reversal is a delocalization of the unfilled 3d-shell electrons on one sublattice just below TC, followed by a gradual localization as the temperature is lowered. This delocalized-localized crossover is supported by muon spectroscopy results, as strong T1 relaxation observed below TC indicates fluctuating internal fields.
AB - Neutron diffraction, magnetization, and muon spin relaxation measurements, supplemented by density functional theory (DFT) calculations are employed to unravel temperature-driven magnetization reversal in inverse spinel Co2VO4. All measurements show a second-order magnetic phase transition at TC=168K to a collinear ferrimagnetic phase. Neutron diffraction measurements reveal two antiparallel ferromagnetic (FM) sublattices, belonging to magnetic ions on two distinct crystal lattice sites, where the relative balance between the two sublattices determine the net FM moment in the unit cell. As the evolution of the ordered moment with temperature differs between the two sublattices, the net magnetic moment reaches a maximum at TNC=138K and reverses its sign at TMR=65K. The DFT results suggest that the underlying microscopic mechanism for the reversal is a delocalization of the unfilled 3d-shell electrons on one sublattice just below TC, followed by a gradual localization as the temperature is lowered. This delocalized-localized crossover is supported by muon spectroscopy results, as strong T1 relaxation observed below TC indicates fluctuating internal fields.
U2 - 10.1103/PhysRevB.105.094408
DO - 10.1103/PhysRevB.105.094408
M3 - Journal article
SN - 1098-0121
VL - 105
JO - Physical Review B
JF - Physical Review B
IS - 9
M1 - 094408
ER -