Cesium-involved electron transfer and electron-electron interaction in high-pressure metallic CsPbI3

Program Document ·

OSTI ID:1845127

Lin, Yu ^[1]

---

1. SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)

Electron-phonon coupling was believed to govern the carrier transport in halide perovskites and related phases. Here we demonstrate that electron-electron interaction 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-to-metal transition occurs, concomitant with the completion of a sluggish structural transition from the one-dimensional (1D) Pnma (δ) phase to a 3D Pmn21 (ε) phase. Deviation from FL behavior is observed in CsPbI3 upon 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 is related to the Cs-involved electron transfer and sudden increase of the 5d state occupation of the high-pressure ε phase. Our study presents a promising strategy for tuning the electronic interaction in halide perovskites for realizing intriguing electronic states.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 1845127
• Report Number(s): Nonr
• Country of Publication: United States
• Language: English