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DOE OSTI · 3011349

Magnetic semiconductors from functionalized Cr 2 ⁢C MXenes

Limbu, Yogendra [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000150718983)·Paudyal, Hari [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000236610826)·da Silva, Eudes Gomes [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000238129331)·Candido, Denis R. [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000267083280)·Flatté, Michael E. [Univ. of Iowa, Iowa City, IA (United States); Eindhoven Univ. of Technology (Netherlands)] (ORCID:0000000150931549)·Paudyal, Durga [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000200600220)
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Abstract

Here, we report an ab initio investigation of functionalized and 3⁢𝑑-electron-doped Cr 2 ⁢C MXenes. Upon functionalization, the Cr 2⁢ C becomes chemically, dynamically, and mechanically stable, and it exhibits magnetic semiconducting behavior. Cr 2 ⁢CF 2 stands out as a wide band gap semiconductor, possessing superexchange 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 Cr 2 ⁢CH 2 is supported by the distorted Cr spin density due to the hydrogen environment. Two magnon branches, associated with two sublattice spins, are found in the ferromagnetic Cr 2 ⁢CO 2 and antiferromagnetic Cr 2 ⁢CF 2 . Depending on the types of 3⁢𝑑-electron dopants and functionalization, Cr 2 ⁢C MXenes (except for Cr 2 ⁢CO 2 ) change from an indirect band gap magnetic semiconductor to different states of electronic and magnetic matter, including an exotic direct band gap magnetic bipolar semiconductor. In addition, we reveal a band inversion between the two highest valence bands in the Fe-doped Cr 2 ⁢CCl 2 .

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2D materials75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYMXeneselectronic structurefirst-principles calculationsmagnetismmagnonsquantum informationspin-phonon couplingtwo-dimensional electron system

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Limbu, Yogendra [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000150718983), Paudyal, Hari [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000236610826), da Silva, Eudes Gomes [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000238129331), Candido, Denis R. [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000267083280), Flatté, Michael E. [Univ. of Iowa, Iowa City, IA (United States); Eindhoven Univ. of Technology (Netherlands)] (ORCID:0000000150931549), Paudyal, Durga [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000200600220). 2025-12-22. Magnetic semiconductors from functionalized Cr 2 ⁢C MXenes. https://doi.org/10.1103/9k4g-kjgf

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