The nontrivial fermions and bosons emerge in the 2D CrBr3 and TiBr3 monolayer.
The second-order topological insulator is characterized by w2=1 and the nontrivial corner states.
The topological magnon insulator demonstrates the magnon edge state and thermal Hall effect.
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| [71] | See Supplemental Information for crystalline structures and phonon dispersion of TiBr3 monolayer, evolution of the magnon spectrum gap with D2 for the CrBr3 monolayer, magnon energy spectrums and thermal Hall conductivity with different D2 and magnetic field B, energy discrete spectrum of a nanoflake for FM CrBr3 monolayer with in-plane magnetization, energy spectrum of hexagonal nanoflake for FM CrBr3 monolayer, energy discrete spectra of the triangular nanoflakes for FM CrBr3 monolayer with different sizes and energy spectrum of irregular nanoflake for FM CrBr3 monolayer. |
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| Zou X., Bai Y., Dai Y., et al. (2025). Experimentally feasible CrBr3 monolayer: Electronic and magnonic topological states correlated with rotation symmetry. The Innovation Materials 3:100109. https://doi.org/10.59717/j.xinn-mater.2024.100109 |
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Crystalline structure of CrBr3 monolayer
The electronic properties of CrBr3 monolayer
The magnonic properties of CrBr3 monolayer
The electronic and magnonic properties of TiBr3 monolayer