Exotic properties and manipulation in 2D semimetal Mn2B2(OH)2: a theoretical study

TL;DR

This theoretical study explores a novel 2D Mn2B2(OH)2 phase with multiple switchable electrical polarizations, linked to band structure splitting and ferroelasticity, showing potential for multi-functional sensing applications.

Contribution

The paper introduces a new alpha-phase of 2D Mn2B2(OH)2 with multiple electrical polarizations and tunable properties, expanding the understanding of 2D magnetic and ferroelastic materials.

Findings

Eighteen distinct electrical polarizations identified.

Polarization switching linked to band structure splitting.

Potential superconductivity suggested by honeycomb lattice.

Abstract

Most functional materials possess one single outstanding property and are limited to be used for a particular purpose. Instead of integrating materials with different functions into one module, designing materials with controllable multi-functions is more promising for the electronic industry. In this study, we investigate an unexplored alpha-phase of two-dimensional (2D) Mn2B2(OH)2 theoretically. Eighteen distinct electrical polarizations, characterized by three different magnitudes and twelve different directions, are found in this phase. The switch of the electrical polarizations is also linked to an observed splitting of band structures between different spin states and the ferroelasticity of the system. The manipulation of these properties can be realized through controlling the alignment of Mn-OH-Mn chains. Additionally, the approximately honeycomb lattice for the atomic layer of boron indicate the potential superconductivity in the system. The diverse and tunable properties make the proposed material as an outstanding candidate for sensing applications at the 2D limit.