Unusual magnetoelectric memory and polarization reversal in the kagome staircase compound N i3V2O8
Abstract
We study the electric polarization of the kagome staircase N i3V2O8 in magnetic fields up to 30 T and report a magnetoelectric memory effect controlled by bias electric fields. The explored ferroelectric phase in 19 -24 T is electrically controlled, whereas the ferroelectric phase in 2 -11 T exhibits unusual memory effects. We determine a characteristic critical magnetic field H3=11 T , below which strong memory exists and the polarization is frozen even in opposite bias fields. But when magnetic fields exceed H3, the frozen polarization is released and polarization reversal appears by tuning bias electric fields. We ascribe these phenomena to the pinning-depinning mechanism: nucleation and the accompanying pinning of chiral domain walls cooperatively induce the frozen behavior; the polarization reversal results from the depinning through the ferroelectrtic-to-paraelectric phase transition in high magnetic fields. Our experimental results reveal that the first-order phase transition plays an important role in these unusual memory effects.
- Publication:
-
Physical Review B
- Pub Date:
- May 2018
- DOI:
- 10.1103/PhysRevB.97.174429
- Bibcode:
- 2018PhRvB..97q4429L