Discovery of enhanced lattice dynamics in a single-layered hybrid perovskite

Abstract

Layered hybrid perovskites have attracted much attention in recent years due to their emergent physical properties and exceptional functional performances, but the coexistence of lattice order and structural disorder severely hinders our understanding of these materials. One unsolved problem regards how the lattice dynamics are affected by the dimensional engineering of the inorganic frameworks and the interaction with the molecular moieties. Here, we address this question by using a combination of high-resolution spontaneous Raman scattering, high-field terahertz spectroscopy, and molecular dynamics simulations. This approach enables us to reveal the structural vibrations and disorder in and out of equilibrium and provides surprising observables that differentiate single- and double-layered perovskites. While no distinct vibrational coherence is observed in double-layer perovskites, we discover that an off-resonant terahertz pulse can selectively drive a long-lived coherent phonon mode through a two-photon process in the single-layered system. This difference highlights the dramatic change in the lattice environment as the dimension is reduced. The present findings pave the way for the ultrafast structural engineering of hybrid lattices as well as for developing high-speed optical modulators based on layered perovskites.

References in corpus (11)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Terahertz-Field-Induced Ferroelectricity in Quantum Paraelectric SrTiO${}_3$
• Directional Anisotropy of the Vibrational Modes in 2D Layered Perovskites
• Vibrational relaxation dynamics in layered perovskite quantum wells
• The tetragonal phase of CH${}_3$NH${}_3$PbI${}_3$ is strongly anharmonic
• Nonlinear THz Control of the Lead Halide Perovskite Lattice
• Decoding Ultrafast Polarization Responses in Lead Halide Perovskites by the Two-Dimensional Optical Kerr Effect
• Ultrafast control of material optical properties via the infrared resonant Raman effect
• The Ultrafast Kerr Effect in Anisotropic and Dispersive Media
• Terahertz Kerr effect in a methylammonium lead bromide perovskite crystal

Cited by in corpus (3)

• Terahertz field-induced metastable magnetization near criticality in FePS3
• Nonlinear THz Control of the Lead Halide Perovskite Lattice
• Quantum beats of exciton-polarons in CsPbI3 perovskite nanocrystals