Ultrafast charge transfer and vibronic coupling in a laser-excited hybrid inorganic/organic interface

Abstract

Hybrid interfaces formed by inorganic semiconductors and organic molecules are intriguing materials for opto-electronics. Interfacial charge transfer is primarily responsible for their peculiar electronic structure and optical response. Hence, it is essential to gain insight into this fundamental process also beyond the static picture. Ab initio methods based on real-time time-dependent density-functional theory coupled to the Ehrenfest molecular dynamics scheme are ideally suited for this problem. We investigate a laser-excited hybrid inorganic/organic interface formed by the electron acceptor molecule 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-quinodimethane (F4TCNQ) physisorbed on a hydrogenated silicon cluster, and we discuss the fundamental mechanisms of charge transfer in the ultrashort time window following the impulsive excitation. The considered interface is $p$-doped and exhibits charge transfer in the ground state. When it is excited by a resonant laser pulse, the charge transfer across the interface is additionally increased, but contrary to previous observations in all-organic donor/acceptor complexes, it is not further promoted by vibronic coupling. In the considered time window of 100~fs, the molecular vibrations are coupled to the electron dynamics and enhance intramolecular charge transfer. Our results highlight the complexity of the physics involved and demonstrate the ability of the adopted formalism to achieve a comprehensive understanding of ultrafast charge transfer in hybrid materials.

References in corpus (11)

• Canonical sampling through velocity-rescaling
• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
• Tightly bound excitons in monolayer WSe2
• Excitons versus electron-hole plasma in monolayer transition metal dichalcogenide semiconductors
• Watching the coherent birth of polaron pairs in conjugated polymers
• Ab initio calculations of ultra-short carrier dynamics in 2D materials: valley depolarization in single-layer WSe${}_2$
• Simulating pump-probe photo-electron and absorption spectroscopy on the attosecond time-scale with time-dependent density-functional theory
• Ab initio Simulation of Optical Limiting: The Case of Metal-Free Phthalocyanine
• Electronic and optical excitations of two-dimensional ZrS${}_2$ and HfS${}_2$ and their heterostructure
• Ultrafast dynamics of photoinduced charge separation

Cited by in corpus (7)

• Understanding real-time time-dependent density-functional theory simulations of ultrafast laser-induced dynamics in organic molecules
• Conditions for electronic hybridization between transition-metal dichalcogenide monolayers and physisorbed carbon-conjugated molecules
• Laser-Controlled Charge Transfer in a Two-Dimensional Organic/Inorganic Optical Coherent Nanojunction
• Laser-Induced Electronic and Vibronic Dynamics in the Pyrene Molecule and its Cation
• Ab initio simulation of laser-induced electronic and vibrational coherence
• Formation of lead halide perovskite precursors in solution: Insight from electronic-structure theory
• Vibronic Couplings and Temperature Effects in the Ultrafast Dynamics of a Charge-Transfer Complex