Room-Temperature Multiferroic Skyrmions in LiNbO3 with enhancement in electric-optical property

TL;DR

This study provides the first experimental evidence of ferroelectrically-induced ferromagnetism in LiNbO3, identifies room-temperature multiferroic skyrmions, and demonstrates a significant enhancement in its electro-optic properties, opening new avenues in spintronics and optoelectronics.

Contribution

First experimental validation of ferroelectrically-induced ferromagnetism and multiferroic skyrmions in LiNbO3, with a notable enhancement in electro-optic effects.

Findings

Evidence of Dzyaloshinskii-Moriya interaction in LiNbO3

Identification of stable multiferroic skyrmions at room temperature

Over 200% enhancement in electro-optic effect

Abstract

LiNbO3 (LN) is renowned for its exceptional ferroelectric properties, particularly its notable linear electro-optical (EO) effect, which is highly advantageous for various applications such as high-speed communication, optical computation, and quantum information processing. Compared to its ferroelectric properties, the magnetism of LN is not attractive enough due to its weak ferromagnetic nature. Theoretical studies suggest that LN may exhibit a novel magnetoelectric coupling via ferroelectrically-induced ferromagnetism. However, this mechanism has not yet been experimentally validated in any materials, presenting significant challenges for research. In this study, we provide the first experimental evidence supporting the mechanism of ferroelectrically-induced ferromagnetism in LN, including observations of the Dzyaloshinskii-Moriya interaction (DMI) and magnetoelectric coupling. Additionally, we have identified various multiferroic skyrmions, within which ferroelectric polarization signals are detectable. These signals can be influenced by the magnetic vortex structures, indicating a magnetoelectric coupling nature. Currently, they are the only multiferroic skyrmions that can keep stable at room temperature. Moreover, these magnetic textures significantly affect the ferroelectric properties, as demonstrated by an enhancement of the linear electro-optic effect of LN by over 200%. Given the novel magnetoelectric coupling mechanism, the potential of multiferroic skyrmions in spintronics and advanced data storage, and the extensive use of LN EO modulators, our research has significant implications for condensed matter physics, multiferroic materials, and optoelectronics.