Cesium-mediated electron redistribution and electron-electron interaction in high-pressure metallic CsPbI3
Abstract
Electron-phonon coupling was believed to govern the carrier transport in halide perovskites and related phases. Here we demonstrate that electron-electron interaction enhanced by Cs-involved electron redistribution plays a direct and prominent role in the low-temperature electrical transport of compressed CsPbI3 and renders Fermi liquid (FL)-like behavior. By compressing δ-CsPbI3 to 80 GPa, an insulator-semimetal-metal transition occurs, concomitant with the completion of a slow structural transition from the one-dimensional Pnma (δ) phase to a three-dimensional Pmn21 (ε) phase. Deviation from FL behavior is observed upon CsPbI3 entering the metallic ε phase, which progressively evolves into a FL-like state at 186 GPa. First-principles density functional theory calculations reveal that the enhanced electron-electron coupling results from the sudden increase of the 5d state occupation in Cs and I atoms. Our study presents a promising strategy of cationic manipulation for tuning the electronic structure and carrier scattering of halide perovskites at high pressure.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 18, 2022
- Source ID
- 10.1038/s41467-022-34786-5
Entities
People
- Feng Ke
- Hemamala Karunadasa
- Hong Yang
- J-J Wen
- Jiejuan Yan
- Ketao Yin
- Nathan Wolf
- Shanyuan Niu
- Wendy L. Mao
- Yan-Kai Tzeng
- Young S Lee
- Yu Lin
Organizations
- United States Department of Energy