Slow Dephasing of Coherent Optical Phonons in Two-dimensional Lead Organic Chalcogenides
arXiv:2409.00180 · doi:10.1021/jacs.4c12643
Abstract
Hybrid organic-inorganic semiconductors with strong electron-phonon interactions provide a programmable platform for developing a variety of electronic, optoelectronic, and quantum materials by controlling these interactions. However, in current hybrid semiconductors, such as halide perovskites, anharmonic vibrations with rapid dephasing hinder the ability to coherently manipulate phonons. Here, we report the observation of long-lived coherent phonons in lead organic chalcogenides (LOCs), a new family of hybrid two-dimensional semiconductors. These materials feature harmonic phonon dynamics despite distorted lattices, combining long phonon dephasing times with tunable semiconducting properties. Dephasing time as long as 75 ps at 10 K, with up to 500 cycles of phonon oscillation between scattering events, was observed, corresponding to a dimensionless harmonicity parameter more than an order of magnitude larger than that of halide perovskites. The phonon dephasing time is significantly influenced by anharmonicity and centrosymmetry, both of which can be tuned through the design of the organic ligands thanks to the direct bonding between the organic and inorganic motifs. This research opens new opportunities for the manipulation of electronic properties with coherent phonons in hybrid semiconductors.
References in corpus (8)
- Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
- Strongly coupled coherent phonons in single-layer MoS
- Vibrational relaxation dynamics in layered perovskite quantum wells
- Terahertz phonon engineering with van der Waals heterostructures
- Strong Coupling of Coherent Phonons to Excitons in Semiconducting Monolayer MoTe
- Room temperature wavelike exciton transport in a van der Waals superatomic semiconductor
- Many-Exciton Quantum Dynamics in a Ruddlesden-Popper Tin Iodide
- Ultrastrong Light-Matter Coupling in 2D Metal-Chalcogenates