26th Australian Institute of Physics Congress and the Australian and New Zealand Conference on Optics and Photonics

First-Principles Investigation of Electron–Phonon-Mediated Superconductivity in Functionalized M$_2$XN$_2$ (M = Transition Metal; X = C, B) Two-Dimensional Monolayers

Not scheduled

20m

Belinda Hutchinson Building (The University of Sydney )

Poster AIP | Condensed Matter & Materials (CMM)

Description

After the successful discovery of MgB$_2$ (Tc= 39K) as a high-temperature superconductor has opened the doors for series of Boron and carbon based 2D models in condensed matter physics. Among different 2D materials, transition metals MXenes and MBenes (M$_2$X, where X = C, B) have been widely explored for their electronic, magnetic, and electrochemical properties, but have yet to be widely explored for their superconducting properties [1]. This work, will systematically explore structural optimization, electronic, and lattice dynamical properties of functionalized MXene- and MBene-derived 2D monolayers such as M$_2$XN$_2$ (where M = transition-metal and X = C, B) by introducing a hydrogenation and nitrogen-functionalization structure using first-principles calculations integrated in Quantum Espresso and aimed at identifying potential high-temperature superconducting materials. Many MXenes/MBenes have been proposed in literature, however, few of them have been stability-checked; here our initial calculations predict the structural and dynamical stability via obtaining the energy converged parameters, and phonon dispersion. Furthermore, to eliminate the pair breaking caused by spin fluctuation, we investigated the magnetic ground state of the stable candidate and screen-out the unpolarized material. The electronic band structure and fatband analysis confirmed the metallic behavior and the high density of state around the Fermi level, which validates these systems as potential for further investigation. Based on these electronic and stability foundations, we are investigating the electron-phonon coupling strength, Eliashberg theroy, and McMillan-Allen-Dynes formula to calculate the Tc of superconductors [2]. Understanding all of these phenomena of functionalizing MXene/MBenes will lead to better understanding and prediction of potential candidate materials as high-Tc superconductors mediated via the electron-phonon interactions, making these systems compelling candidates for superconductivity.

References

1. A. Sangeetha and S. Shanmugan, Novel Energy Storage and Conversion Technologies for Two-Dimensional MX- enes and MBenes (2025).

2. R. Long et al., Phys. Rev. B 113, 134506 (2026).