3:1 magnetization plateau and suppression of ferroelectric polarization in an Ising chain multiferroic

TL;DR

This study investigates the magnetic and ferroelectric properties of a Ca$_3$Co$_{2-x}$Mn$_x$O$_6$ Ising chain multiferroic under high magnetic fields, revealing a 3:1 magnetization plateau and polarization suppression linked to spin state transitions.

Contribution

It demonstrates the magnetic field-induced spin state transitions and polarization suppression in a multiferroic Ising chain, highlighting the coupling between magnetic order and ferroelectricity.

Findings

Successive metamagnetic transitions observed

Magnetization plateau at 3:1 ratio identified

Electric polarization is suppressed in certain spin states

Abstract

Ferroelectric Ising chain magnet Ca$_3$Co$_{2-x}$Mn$_x$O$_6$ ($x\simeq$0.96) was studied in magnetic fields up to 33 T. Magnetization and neutron scattering measurements reveal successive metamagnetic transitions from the zero-field $\uparrow \uparrow \downarrow \downarrow$ spin configuration to the $\uparrow \uparrow \uparrow \downarrow$ state with a broad magnetization plateau, and then to the $\uparrow \uparrow \uparrow \uparrow$ state. The absence of hysteresis in these plateaus reveals an intriguing coupling between the intra-chain state and the three-dimensional geometrically frustrated magnetic system. Inversion symmetry, broken in the $\uparrow \uparrow \downarrow \downarrow$ state, is restored in the $\uparrow \uparrow \uparrow \downarrow$ state, leading to the complete suppression of the electric polarization driven by symmetric superexchange.