We have reconstructed the quantum state of optical pulses containing single photons using the method of phase-randomized pulsed optical homodyne tomography. The single-photon Fock state 1> was prepared using conditional measurements on photon pairs born in the process of parametric down-conversion. A probability distribution of the phase-averaged electric… (More)
A pulsed, balanced homodyne detector has been developed for precise measurement of the electric field quadratures of pulsed optical quantum states. A high level of common mode suppression (>85 dB) and low electronic noise (730 electrons per pulse) provide a signal-to-noise ratio of 14 dB for measurement of the quantum noise of individual pulses.… (More)
We present two applications of a single nitrogen vacancy center in a nanodiamond as quantum probe for plasmonic nanostructures. Coupling to the nanostructures is achieved in a highly controlled manner by picking up a pre-characterized nanocrystal with an atomic force microscope and placing it at the desired position. Local launching of single excitations… (More)
1 Introduction In the last decade quantum information processing (QIP) has become one of the major research topics in physics . Here, the main problem is to realize platforms in which complex quantum systems are well isolated from the environment and perfecly controlled at the same time. Many groups all over the world intend to realize such systems based… (More)
The authors report single-photon emission from InGaAs quantum dots grown by droplet epitaxy on (100) GaAs substrates using a solid-source molecular beam epitaxy system at elevated substrate temperatures above 400°C without post-growth annealing. High-resolution micro-photoluminescence spectroscopy exhibits sharp excitonic emissions with lifetimes ranging… (More)
We present integrated and highly efficient single photon sources based on defect-centers in nanodiamonds as fundamental components for future implementations of quantum information technologies. We achieve count rates of 2.4 Mcts/s and source efficiencies of 20%.