Magnetic phase transition inV2O3nanocrystals

Abstract

Magnetic phase transition in V2O3 nanocrystalsV 2 O 3 nanocrystals can be synthesized through hydrothermal reduction in VO͑OH͒ 2 using hydrazine as a reducing agent. Addition of different ligands to the reaction produces nanoparticles, nanorods, and nanoplatelets of different sizes. Small nanoparticles synthesized in this manner show suppression of the magnetic phase transition to lower temperatures. Using muon spin relaxation spectroscopy and synchrotron x-ray diffraction, we have determined that the volume fraction of the high-temperature phase, characterized by a rhombohedral structure and paramagnetism, gradually declines with decreasing temperature, in contrast to the sharp transition observed in bulk V 2 O 3 .

Volume-wise destruction of the antiferromagnetic Mott insulating state through quantum tuning

“…The curious stretching of the magnetic transition observed in RENiO 3 is also seen in V 2 O 3 for larger applied pressures, in agreement with an earlier high-pressure NMR study33. This stretched transition is also somewhat similar to that observed in V 2 O 3 nanocrystals34, although surface area effects are likely the cause in that case. These results demonstrate that the AF phases in RENiO 3 and V 2 O 3 have identical behaviour in all key aspects near the QPT.…”

Facile synthesis and phase transition of V2O3 nanobelts

“…Different from V2O3 single crystal, the crystallographic, electronic, and magnetic transitions in nanomaterials may not occur simultaneously due to finite size effect, stress and defect states in these nanomaterials. [15,17] To further explore the phase transition of the V2O3 nanobelts, we also utilized variable-temperature Raman spectroscopy (VT-Raman) to measure the Tc of individual V2O3 nanobelts. Compared to other methods such as variable-temperature XRD, [9] optical [18] and electrical measurements, [14] VT-Raman is capable of detecting individual material with high spatial resolution and does not require complicated lithographic fabrications.…”

Metal-Insulator Phase Transition and Structural Stability in ‘Sb’ Doped CaMnO3 Perovskite

“…The 'c' axis also found to undergo an elongation from 7.5401 Å to 7.7405 Å for doping concentration of 0.3 ≤ x ≥ 0.1. Increase in the lattice parameter for the concentration x =0.2 to 0.4, indicates low chemical pressure induced by doping giving rise to high transition temperature [16].…”