We report an \textit{ab initio} investigation of functionalized and 3d-electrons doped Cr2C MXenes. Upon functionalization, the Cr2C becomes chemically, dynamically, and mechanically stable, and it exhibits magnetic semiconducting behavior. Cr2CF2 stands out as a wide band gap semiconductor, possessing super exchange interaction mediated by F atoms within the layer, however, the applied strain transforms it from an indirect to a direct band gap semiconductor. Strong spin-phonon coupling found in Cr2CH2 is supported by the distorted Cr spin density due to hydrogen environment. Two magnon branches, associated with two sub-lattice spins, are found in the ferromagnetic Cr2CO2 and antiferromagnetic Cr2CF2. Depending on the types of 3d-electron dopants and functionalization, Cr2C MXenes (except for Cr2CO2) change from the indirect band gap magnetic semiconductor to different states of electronic and magnetic matter including exotic direct band gap magnetic bipolar semiconductor. In addition, we reveal a band inversion between the two highest valence bands in the Fe-doped Cr2CCl2.
@article{arxiv.2503.15695,
title = {Functionalized Cr$_2$C MXenes: Novel Magnetic Semiconductors},
author = {Yogendra Limbu and Hari Paudyal and Eudes Gomes da Silva and Denis R. Candido and Michael E. Flatté and Durga Paudyal},
journal= {arXiv preprint arXiv:2503.15695},
year = {2025}
}
Comments
7 pages, 6 figures, 15 pages supplemental material that contains details of magnon calculations and 19 supporting figures