Lattice dynamics and ferroelectric properties of the nitride perovskite ${\mathrm{LaWN}}_{3}$
| Autor: | Fang, Yue-Wen, Fisher, Craig A. J., Kuwabara, Akihide, Shen, Xin-Wei, Ogawa, Takafumi, Moriwake, Hiroki, Huang, Rong, Duan, Chun-Gang |
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| Rok vydání: | 2023 |
| Předmět: | |
| Zdroj: | Phys. Rev. B 95, 014111 (2017) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevB.95.014111 |
| Popis: | Using first-principles calculations we examine the crystal structures and phase transitions of nitride perovskite LaWN$_3$. Lattice dynamics calculations indicate that the ground-state structure belongs to space group $R3c$. Two competitive phase transition pathways are identified which are characterized by symmetry-adapted distortion modes. The results suggest that $R3c$ LaWN$_3$ should be an excellent ferroelectric semiconductor: its large spontaneous polarization of around 61 $\mu$C/cm$^2$ is comparable to that of PbTiO$_3$, and its band gap is about 1.72 eV. Ferroelectricity is found to result from the \emph{B}-site instability driven by hybridization between W-5$d$ and N-2$p$ orbitals. These properties make LaWN$_3$ an attractive candidate material for use in ferroelectric memory devices and photovoltaic cells. Comment: 13 pages, 8 figures in main text and 5 figures in supplementary |
| Databáze: | arXiv |
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