Related papers: Ultrafast Depopulation of a Quantum Dot by LA-phon…
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…
Semiconductor quantum dots can emit antibunched, single photons on demand with narrow linewidths. However, the observed linewidths are broader than lifetime measurements predict, due to spin and charge noise in the environment. This noise…
We present rigorous and intuitive master equation models to study on-demand single photon sources from pulse-excited quantum dots coupled to cavities. We consider three methods of source excitation: resonant pi-pulse, off-resonant…
We analyze the main physical processes in quantum cascade lasers with spatial separation between the region of photon radiation and LO phonon emission providing depopulation of the lower level of the optical transition. Our purpose is to…
We explore the possibility to entangle an excitonic two-level system in a semiconductor quantum dot (QD) with a cavity defined on a photonic crystal by sweeping the cavity frequency across its resonance with the exciton transition. The…
We present a simple technique to reduce the emission rate of higher-order photon events from pulsed spontaneous parametric down-conversion. The technique uses extra-cavity control over a mode locked ultrafast laser to simultaneously…
A quantum dot can be used as a source of one- and two-photon states and of polarisation entangled photon pairs. The emission of such states is investigated from the point of view of frequency-resolved two-photon correlations. These follow…
When an electron-hole pair is optically excited in a semiconductor quantum dot the host crystal lattice needs to adapt to the presence of the generated charge distribution. Therefore the coupled exciton-phonon system has to establish a new…
An ultrafast atomic motion of a photo-induced coherent phonon of bismuth at low temperatures was directly observed with time-resolved x-ray diffraction. A cryostat with a window that is transparent to both optical lasers and x-rays enabled…
It is demonstrated how the exciton and the biexciton state of a quantum dot can be prepared with high fidelity on a picosecond time-scale by driving the dot with a strong laser pulse that is tuned above the exciton resonance for exciton…
Coupling a resonator to a superconducting qubit enables various operations on the qubit, including dispersive readout and unconditional reset. The speed of these operations is limited by the external decay rate of the resonator. However,…
Employing the ultrafast control of electronic states of a semiconductor quantum dot in a cavity, we introduce a novel approach to achieve on-demand emission of single photons with almost perfect indistinguishability and photon pairs with…
We investigate theoretically acoustic phonon induced decoherence in quantum dots. We calculate the dephasing of fundamental (interband or intraband) optical transitions due to real and virtual transitions with higher energy levels. Up to…
The ability to control and exploit quantum coherence and entanglement drives research across many fields ranging from ultra-cold quantum gases to spin systems in condensed matter. Transcending different physical systems, optical approaches…
We calculate the longitudinal-acoustic phonon scattering rate for a vertical double quantum dot system with weak lateral confinement and show that a strong modulation of the single-electron excited states lifetime can be induced by an…
We report high-energy mid-infrared pulse generation by Q-switching of dysprosium-doped fiber lasers for the first time. Two different modulation techniques are demonstrated. Firstly, using active acousto-optic modulation, pulses are…
We study the electronic relaxation in a quantum dot within the polaron approach, by focusing on the {\it reversible} anharmonic decay of longitudinal optical (LO) phonons forming the polaron into longitudinal acoustic (LA) phonons. The…
We study the quantum dynamics of a two-level system driven by a pulse that starts near-resonant for small amplitudes, yielding nonadiabatic evolution, and induces an adiabatic evolution for larger amplitudes. This problem is analyzed in…
Single-photon sources play a key role in photonic quantum technologies. Semiconductor quantum dots can emit indistinguishable single photons under resonant excitation. However, the resonance fluorescence technique typically requires…
High-dimensional quantum information processing promises capabilities beyond the current state of the art, but addressing individual information-carrying modes presents a significant experimental challenge. Here we demonstrate effective…