TY  - INPR
A1  - Müller, Stefan
A1  - Draeger, Simon
A1  - Ma, Kiaonan
A1  - Hensen, Matthias
A1  - Kenneweg, Tristan
A1  - Pfeiffer, Walter
A1  - Brixner, Tobias
T1  - Fluorescence-Detected Two-Quantum and One-Quantum-Two-Quantum 2D Electronic Spectroscopy
T2  - Journal of Physical Chemistry Letters
N2  - We demonstrate two-quantum (2Q) coherent two-dimensional (2D)electronic spectroscopy using a shot-to-shot-modulated pulse shaper and fluorescence detection. Broadband collinear excitation is realized with the supercontinuum output of an argon-filled hollow-core fiber, enabling us to excite multiple transitions simultaneously in the visible range. The 2Q contribution is extracted via a three-pulse sequence with 16-fold phase cycling and simulated employing cresyl violet as a model system. Furthermore, we report the first experimental realization of one-quantum−two-quantum (1Q-2Q) 2D spectroscopy, offering less congested spectra as compared with the 2Q implementation. We avoid scattering artifacts and nonresonant solvent contributions by using fluorescence as the observable. This allows us to extract quantitative information about doubly excited states that agree with literature expectations. The high sensitivity and background-free nature of fluorescence detection allow for a general applicability of this method to many other systems.
KW  - Zweidimensionale Spektroskopie
KW  - elektronisch angeregte Zustände
KW  - Doppelquantenkohärenz
KW  - Fluoreszenz
KW  - Optische Spektroskopie
KW  - Molekülzustand
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-173468
UR  - https://pubs.acs.org/doi/10.1021/acs.jpclett.8b00541
ER  - 
TY  - INPR
A1  - Fersch, Daniel
A1  - Malý, Pavel
A1  - Rühe, Jessica
A1  - Lisinetskii, Victor
A1  - Hensen, Matthias
A1  - Würthner, Frank
A1  - Brixner, Tobias
T1  - Single-Molecule Ultrafast Fluorescence-Detected Pump–Probe Microscopy
N2  - We introduce fluorescence-detected pump–probe microscopy by combining a wavelength-tunable ultrafast laser with a confocal scanning fluorescence microscope, enabling access to the femtosecond time scale on the micrometer spatial scale. In addition, we obtain spectral information from Fourier transformation over excitation pulse-pair time delays. We demonstrate this new approach on a model system of a terrylene bisimide (TBI) dye embedded in a PMMA matrix and acquire the linear excitation spectrum as well as time-dependent pump–probe spectra simultaneously. We then push the technique towards single TBI molecules and analyze the statistical distribution of their excitation spectra. Furthermore, we demonstrate the ultrafast transient evolution of several individual molecules, highlighting their different behavior in contrast to the ensemble due to their individual local environment. By correlating the linear and nonlinear spectra, we assess the effect of the molecular environment on the excited-state energy.
KW  - Fluoreszenz
KW  - Ultrafast spectroscopy
KW  - Single-molecule microscopy
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-313485
ER  -