Top Curr Chem (Z) (2018) 376:10
1 3
mechanisms, photo-induced coherent oscillations associated with electronic and
vibrational couplings, and complex chemical reactions (Fig. 1).
Keywords Two-dimensional electronic spectroscopy · Heterogeneity · Energy
transfer · Vibronic coupling · Photoreactivity
1 Introduction
Two-dimensional electronic spectroscopy (2DES) can be defined as the “ultimate”
time-resolved nonlinear optical experiment, since it measures both the real (absorptive) and imaginary (dispersive) parts of the complex third-order nonlinear polarization response [9]. 2DES has shown to be more powerful than one-dimensional
four-wave-mixing measurements like transient absorption (often called pump–probe
spectroscopy). In a formal description of transient absorption measurements based
on the framework of nonlinear optics, the pump beam electric field interacts twice
with the sample to photo-excite a fraction of the chromophores into electronic
excited states. These two interactions simply represent the product of the transition
dipole connecting the ground state to an excited state with its complex conjugate to
give the probability of pump absorption. A probe pulse arrives after a variable delay
T to stimulate a signal field that is detected as a change in transmission of the probe.
2DES experiments provide simultaneously high temporal and spectral resolution [10]. The excitation frequency is resolved in 2DES by delaying the two ultrafast
excitation pulses with an interferometric resolution. Any other third-order nonlinear
spectroscopy (i.e., transient absorption) is contained in the 2DES map (Fig. 2) where
the emission detection is followed along the waiting time. The main breakthrough of
2DES resides in the disentanglement of processes in systems with multiple interacting components [3, 4, 11–14].
Fig. 1 Main fields impacted by two-dimensional electronic spectroscopy (2DES) in condensed phase.
The major discoveries of each field will be described in different paragraphs
28
Reprinted from the journal
1 3
mechanisms, photo-induced coherent oscillations associated with electronic and
vibrational couplings, and complex chemical reactions (Fig. 1).
Keywords Two-dimensional electronic spectroscopy · Heterogeneity · Energy
transfer · Vibronic coupling · Photoreactivity
1 Introduction
Two-dimensional electronic spectroscopy (2DES) can be defined as the “ultimate”
time-resolved nonlinear optical experiment, since it measures both the real (absorptive) and imaginary (dispersive) parts of the complex third-order nonlinear polarization response [9]. 2DES has shown to be more powerful than one-dimensional
four-wave-mixing measurements like transient absorption (often called pump–probe
spectroscopy). In a formal description of transient absorption measurements based
on the framework of nonlinear optics, the pump beam electric field interacts twice
with the sample to photo-excite a fraction of the chromophores into electronic
excited states. These two interactions simply represent the product of the transition
dipole connecting the ground state to an excited state with its complex conjugate to
give the probability of pump absorption. A probe pulse arrives after a variable delay
T to stimulate a signal field that is detected as a change in transmission of the probe.
2DES experiments provide simultaneously high temporal and spectral resolution [10]. The excitation frequency is resolved in 2DES by delaying the two ultrafast
excitation pulses with an interferometric resolution. Any other third-order nonlinear
spectroscopy (i.e., transient absorption) is contained in the 2DES map (Fig. 2) where
the emission detection is followed along the waiting time. The main breakthrough of
2DES resides in the disentanglement of processes in systems with multiple interacting components [3, 4, 11–14].
Fig. 1 Main fields impacted by two-dimensional electronic spectroscopy (2DES) in condensed phase.
The major discoveries of each field will be described in different paragraphs
28
Reprinted from the journal