Single-molecule time-resolved spectroscopy in a tunable STM nanocavity

0585165 - FZÚ 2025 RIV US eng J - Journal Article
Doležal, Jiří - Sagwal, Amandeep - de Campos Ferreira, Rodrigo Cezar - Švec, Martin
Single-molecule time-resolved spectroscopy in a tunable STM nanocavity.
Nano Letters. Roč. 24, č. 5 (2024), s. 1629-1634. ISSN 1530-6984. E-ISSN 1530-6992
R&D Projects: GA MŠMT LM2023051; GA ČR(CZ) GA22-18718S
Institutional support: RVO:68378271
Keywords : room-temperature * fluorescence * TEPL * STM * photoluminescence * nanocavity * TCSPC * phthalocyanine
OECD category: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)
Impact factor: 10.8, year: 2022
Method of publishing: Open access

The confinement between a tip and sample in a scanning tunneling microscope creates a tunable nanocavity, an ideal platform for exploring the yields and excitation decay rates of single-molecule emitters, depending on their coupling strength to the nanocavity. With such a setup, we determine the excitation lifetimes from the direct time-resolved measurements of phthalocyanine fluorescence decays, decoupled from the metal substrates by ultrathin NaCl layers. We find that when the tip is approached to single molecules, their lifetimes are reduced to the picosecond range due to the effect of coupling with the tip-sample nanocavity. On the other hand, ensembles of the adsorbed molecules measured without the nanocavity manifest nanosecond-range lifetimes. This approach overcomes the drawbacks associated with the estimation of lifetimes for single molecules from their respective emission line widths.
Permanent Link: https://hdl.handle.net/11104/0352909