Anomaly in structural noncentrosymmetry around TN n bulk and nanoscale BiFeO3

Sudipta Goswami (1) , Dipten Bhattacharya (1) , Gail N. Iles (2) , Barnali Ghosh (3) , Anastasiia A. Prytuliak (4) , Benoît Malard (4) , Gopes C. Das (5) , Bachir Ouladdiaf (4) , Tapan Chatterji (4)

1 CSIR Central Glass and Ceramic Research Institute
2 HZB - Helmholtz-Zentrum Berlin für Materialien und Energie GmbH = Helmholtz Centre Berlin for Materials and Energy = Centre Helmholtz de Berlin pour les matériaux et l'énergie
3 SN Nose National Centre for Basic Science
4 ILL - Institut Laue-Langevin
5 Jadavpur University

Using high resolution powder neutron diffraction data, we show that there is a distinct anomaly in the structural noncentrosymmetry around the magnetic transition point TN for bulk and nanoscale BiFeO3. It appears that the structural noncentrosymmetry - which gives rise to the ferroelectric polarization - is suppressed anomalously by ~1% (of the average noncentrosymmetry at above the magnetic transition) in the bulk sample and by ~12% in the nanoscale sample as the magnetic transition is approached from higher temperature. This observation shows that the multiferroic coupling improves in the nanoscale sample which is expected to brighten the application prospects of nanoscale BiFeO3 in nanospintronics-based sensor devices.

Mots clés: Ferroics; Structural noncentrosymmetry; Powder neutron diffraction; Nanoscale BiFeO3

Domaines: Matériaux

Sudipta Goswami, Dipten Bhattacharya, Gail N. Iles, Barnali Ghosh, Anastasiia A. Prytuliak, et al.. Anomaly in structural noncentrosymmetry around TN n bulk and nanoscale BiFeO3. Powder Diffraction, 2013, 28 (S2), pp.S94-S105. ⟨10.1017/S0885715613001115⟩. ⟨hal-02141804⟩