Diverse edge states of nanoribbons and excitonic insulator states of the monolayer Ta2Ni3Te5

TL;DR

This study uses first-principles calculations to reveal the tunable electronic, magnetic, and excitonic properties of Ta2Ni3Te5 nanoribbons and monolayers, highlighting their potential for advanced nanoelectronic applications.

Contribution

It demonstrates the diverse edge states and excitonic insulator behavior of Ta2Ni3Te5, a layered transition metal chalcogenide, using advanced computational methods.

Findings

Nanoribbons exhibit tunable electronic and magnetic properties.

Monolayer is identified as an excitonic insulator with high exciton binding energy.

Properties are controlled by edge composition, ribbon width, and saturation.

Abstract

Ta2Ni3Te5, a layered transition metal chalcogenide with quasi-one-dimensional electronic states, exhibits rich topological and correlated phenomena. Using first-principles calculations, we explore Ta2Ni3Te5 nanoribbons, demonstrating tunable electronic and magnetic properties-ranging from metallic to semimetallic and semiconducting (band gaps of 29.7-60.8 meV), and from ferromagnetic to antiferromagnetic-controlled by edge (Ni or Ta), ribbon width, and H/F saturation. Additionally, GW and Bethe-Salpeter equation (BSE) calculations, complemented by metaGGA-based modified BSE, reveal that the Ta2Ni3Te5 monolayer is an excitonic insulator, with an exciton binding energy exceeding its band gap. These diverse properties position Ta2Ni3Te5 nanoribbons and monolayers as promising candidates for nanoelectronics, spintronics, and optoelectronics, motivating further experimental exploration.