Symmetry-Engineering-Induced In-Plane Polarization Enhancement in Ta<sub>2</sub>NiS<sub>5</sub>/CrOCl van der Waals Heterostructure
oleh: Yue Su, Peng Chen, Xiangrui Xu, Yufeng Zhang, Weiwei Cai, Gang Peng, Xueao Zhang, Chuyun Deng
| Format: | Article |
|---|---|
| Diterbitkan: | MDPI AG 2023-11-01 |
Deskripsi
Van der Waals (vdW) interfaces can be formed via layer stacking regardless of the lattice constant or symmetry of the individual building blocks. Herein, we constructed a vdW interface of layered Ta<sub>2</sub>NiS<sub>5</sub> and CrOCl, which exhibited remarkably enhanced in-plane anisotropy via polarized Raman spectroscopy and electrical transport measurements. Compared with pristine Ta<sub>2</sub>NiS<sub>5</sub>, the anisotropy ratio of the Raman intensities for the B<sub>2g</sub>, <sup>2</sup>A<sub>g</sub>, and <sup>3</sup>A<sub>g</sub> modes increased in the heterostructure. More importantly, the anisotropy ratios of conductivity and mobility in the heterostructure increased by one order of magnitude. Specifically speaking, the conductivity ratio changed from ~2.1 (Ta<sub>2</sub>NiS<sub>5</sub>) to ~15 (Ta<sub>2</sub>NiS<sub>5</sub>/CrOCl), while the mobility ratio changed from ~2.7 (Ta<sub>2</sub>NiS<sub>5</sub>) to ~32 (Ta<sub>2</sub>NiS<sub>5</sub>/CrOCl). Such prominent enhancement may be attributed to the symmetry reduction caused by lattice mismatch at the heterostructure interface and the introduction of strain into the Ta<sub>2</sub>NiS<sub>5</sub>. Our research provides a new perspective for enhancing artificial anisotropy physics and offers feasible guidance for future functionalized electronic devices.