Fluorescence-Detected Two-Dimensional Electronic Spectroscopy of a Single Molecule

Title data

Jana, Sanchayeeta ; Durst, Simon ; Lippitz, Markus:
Fluorescence-Detected Two-Dimensional Electronic Spectroscopy of a Single Molecule.
In: Nano Letters. Vol. 24 (2024) Issue 40 . - pp. 12576-12581.
ISSN 1530-6992
DOI: https://doi.org/10.1021/acs.nanolett.4c03559

Project information

Abstract in another language

Single-molecule fluorescence spectroscopy is a powerful method that avoids ensemble averaging, but its temporal resolution is limited by the fluorescence lifetime to nanoseconds at most. At the ensemble level, two-dimensional spectroscopy provides insight into ultrafast femtosecond processes, such as energy transfer and line broadening, even beyond the Fourier limit, by correlating pump and probe spectra. Here, we combine these two techniques and demonstrate coherent 2D spectroscopy of individual dibenzoterrylene (DBT) molecules at room temperature. We excite the molecule in a confocal microscope with a phase-modulated train of femtosecond pulses and detect the emitted fluorescence with single-photon counting detectors. Using a phase-sensitive detection scheme, we were able to measure the nonlinear 2D spectra of most of the DBT molecules that we studied. Our method is applicable to a wide range of single emitters and opens new avenues for understanding energy transfer in single quantum objects on ultrafast time scales.