相关论文: Quantum dynamics of photophysical aggregates in co…
The photophysics of $\pi$-conjugated polymers has been of considerable interest over the last three decades because of their organic semiconductor properties. Primary photoexcitations, Frenkel excitons, can be probed optically by means of…
We present theoretical and experimental results showing the effects of incoherent population mixing on two-dimensional (2D) coherent excitation spectra that are measured via a time-integrated population and phase-sensitive detection. The…
We have previously demonstrated that in the context of two-dimensional (2D) coherent electronic spectroscopy measured by phase modulation and phase-sensitive detection, an \emph{incoherent} nonlinear response, due to pairs of…
Organic semiconductors have the remarkable property that their optical excitation not only generates charge-neutral electron-hole pairs (excitons) but also charge-separated polaron pairs with high yield. The microscopic mechanisms…
Reduced abstract. This Thesis explores emergent cooperative phenomena in collective light-matter systems. We study ensembles of interacting quantum emitters coherently driven by a laser field and coupled to photonic structures, focusing on…
Pi-conjugated segments - chromophores - constitute the electronically active units of polymer materials used in organic electronics. To elucidate the effect of bending of these linear moieties on elementary electronic properties such as…
The homogeneous spectral linewidth associated with light-matter interactions is a fundamental descriptor of the optical properties of materials, governed by the quantum dynamics of the condensed-matter system. We discuss here that the…
Similarly-charged polymers in solution, known as polyelectrolytes, are known to form aggregated structures in the presence of oppositely charged counterions. Understanding the dependence of the equilibrium phases and the dynamics of the…
Recently a variety of $\pi$-conjugated polymers have been developed and essayed for a number of applications such as organic light-emitting diodes, organic field-effect transistors, organic photovoltaics, and sensors. Is central for these…
Collective excited states form in organic two-dimensional layers through the Coulomb coupling of the molecular transition dipole moments. They manifest as characteristic strong and narrow peaks in the excitation and emission spectra that…
Photonic condensates are complex systems exhibiting phase transitions due to the interaction with their molecular environment. Given the macroscopic number of molecules that form a reservoir of excitations, numerical simulations are…
By means of multicanonical computer simulations, we investigate thermodynamic properties of the aggregation of interacting semiflexible polymers. We analyze a mesoscopic bead-stick model, where nonbonded monomers interact via Lennard-Jones…
Until recently it was believed that photosynthesis, a fundamental process for life on earth, could be fully understood with semi-classical models. However, puzzling quantum phenomena have been observed in several photosynthetic…
Quantifying and controlling the coherent dynamics and couplings of optically active excitations in solids is of paramount importance in fundamental research in condensed matter optics and for their prospective optoelectronic applications in…
The primary steps of photosynthesis rely on the generation, transport, and trapping of excitons in pigment-protein complexes (PPCs). Generically, PPCs possess highly structured vibrational spectra, combining many discrete intra-pigment…
In high-performance solar cells based on polymeric semiconductors, the mechanism of photocarrier generation on $<100$-fs timescales is yet to be unravelled. In particular the dynamics of early-time electronic coupling between excitons on…
Inter- or intramolecular coupling processes between chromophores such as excimer formation or H- and J-aggregation are crucial to describing the photophysics of closely packed films of conjugated polymers. Such coupling is highly distance…
Understanding of the precise mechanisms of high-temperature superconductivity is elusive. In particular, in order to solve the puzzle of the pairing mechanism, it is important to understand the detailed nature of the excitations at energies…
We report a conceptually straightforward witness that isolates coherent electronic oscillations from their vibronic counterparts in nonlinear optical spectra of molecular aggregates: Coherent oscillations as a function of waiting time in…
We design and synthesize unentangled associative polymers carrying unprecedented high fractions of stickers, up to eight per Kuhn segment, that can form strong pairwise hydrogen bonding of $\sim20k_BT$ without microphase separation. The…