相关论文: Coherent Excitonic Quantum Beats in Time-Resolved …
We investigate the exciton dynamics in an exactly solvable two-band model for semiconductors. The model incorporates light-matter, electron-electron and electron-phonon interactions, and captures exciton formation as well as the transition…
Despite major experimental progresses in time-resolved and angle-resolved photoemission spectroscopy, a quantitative, microscopic framework for interpreting exciton-induced modifications of electronic band structures -- applicable even…
We discuss the potential creation and measurement of coherences in both dispersive solids and qubit-like single levels using current generation time- and angle-resolved photoemission technology. We show that in both cases, when both the…
Oscillatory signals from coherently excited phonons are regularly observed in ultrafast pump-probe experiments on condensed matter samples. Electron-phonon coupling implies that coherent phonons also modulate the electronic band structure.…
Coherence and de-coherence are the most fundamental steps that follow the initial photo-excitation occurring in typical Pump&Probe experiments. Indeed, the initial external laser pulse transfers coherence to the system in terms of creation…
Motivated by recent experimental measurement of the intrinsic excitonic wave-function in 2D Transition-metal dichalcogenides (TMDs) by angle-resolved photoemission spectroscopy (ARPES), we developed a theoretical study to resolve some…
Optical excitation and control of excitonic wavepackets in organic molecules is the basis to energy conversion processes. To gain insights into such processes, it is essential to establish the relationship between the coherence timescales…
We calculate the {\em exact} time-resolved ARPES spectrum of a two-band model semiconductor driven out of equilibrium by resonant and nonresonant laser pulses, highlighting the effects of phonon-induced decoherence and relaxation. {\em…
The strong confinement of semiconductor excitons in a quantum dot gives rise to atom-like behavior. The full benefit of such a structure is best observed in resonant excitation where the excited state can be deterministically populated and…
Ultrafast pump-probe technique is a powerful tool to understand and manipulate properties of materials for designing novel quantum devices. An intense, single cycle terahertz pulse can change the intrinsic properties of semiconductor…
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…
The transient signals derived from femtosecond pump-probe experiments are analyzed in terms of the coherent evolution of the energy levels perturbed by the excitation pulse. The model system is treated as the sum of independent two-level…
The dynamics of atomic levels resonantly coupled by a coherent and intense short high-frequency laser pulse is discussed and it is advocated that this dynamics is sensitively probed by measuring the spectra of the particles emitted. It is…
Non-equilibrium photon correlations of coherently excited single quantum systems can reveal their internal quantum dynamics and provide spectroscopic access. Here we propose and discuss the fundamentals of a coherent photon coincidence…
In the past decade, the advent of time-resolved spectroscopic tools has provided a new ground to explore fundamental interactions in solids and to disentangle degrees of freedom whose coupling leads to broad structures in the frequency…
Time-resolved photoemission orbital tomography (tr-POT) offers unique possibilities for tracing molecular electron dynamics. The recorded pump-induced changes of the angle-resolved photoemission intensities allow to characterize unoccupied…
Angle-resolved photoemission spectroscopy (ARPES) -- with its exceptional sensitivity to both the binding energy and momentum of valence electrons in solids -- provides unparalleled insights into the electronic structure of quantum…
Time- and angle-resolved photoemission spectroscopy (trARPES) is a powerful spectroscopic method to measure the ultrafast electron dynamics directly in momentum-space. However, band gap materials with exceptional strong Coulomb interaction…
Coherent phonons can greatly vary light-matter interaction in semiconductor nanostructures placed inside an optical resonator on an ultrafast time scale. For an ensemble of quantum dots as active laser medium phonons are able to induce a…
Free electrons provide a powerful tool to probe material properties at atomic-scale spatial resolution. Recent advances in ultrafast electron microscopy enable the manipulation of free electron wavefunctions using laser pulses. It would be…