Typical emitters such as molecules, quantum dots and semiconductor quantum wells have slow spontaneous emission with lifetimes of 1-10 ns, creating a mismatch with high-speed nanoscale optoelectronic devices such as light-emitting diodes, single-photon sources and lasers. Here we experimentally demonstrate an ultrafast (<11 ps) yet efficient source of spontaneous emission, corresponding to an e...

A generalized formulation of spontaneous emission and super-radiance effects in a free-electron laser is presented. We consider a stream of electrons of arbitrary temporal duration propagating through the undulator. The sum of the undulator synchrotron radiation emitted by individual wiggling electrons entering the wiggler at random, results in shot-noise in the radiation field. Using the waveg...

We report on measurement of momentum transfer to an atomic sodium beam by a standingwave laser field. Experiments were performed in two regimes: 1) the regime in which spontaneous emission is negligible; and 2) the regime in which the effects of spontaneous decay dominate the momentum transfer process. In the first regime, we observe diffraction of the atomic beam: the near-resonant Kapitza-Dir...

We have performed time-resolved spectroscopy on InAs quantum dot ensembles in photonic crystal membranes. The influence of the photonic crystal is investigated by varying the lattice constant systematically. We observe a strong slow down of the quantum dots’ spontaneous emission rates as the two-dimensional bandgap is tuned through their emission frequencies. The measured band edges are in full...

Photograph of a mechanically flexible 2D-DFB laser made from the conjugated polymer MeLPPP. The laser is optically pumped well above the threshold for amplified spontaneous emission. The complex far-field emission pattern (blue-green) results from a large detuning between the resonance wavelength and the gain maximum. • A nearly diffraction limited surface emitting conjugated polymer laser util...