Our paper entitled An artificial Rb atom in a semiconductor with lifetime-limited linewidth was published in Physical Review B. This work, a collaboration with Philipp Treutlein (Basel), Armando Rastelli (Linz), Fei Ding and Oliver Schmidt (Dresden), describes single photon creation using a “droplet” quantum dot. Surprisingly, our first attempts at creating spectrally narrow single photons with this system were successful: the quantum dot linewidth is just 1.42 GHz corresponding to the transform limit for one quantum dot we probed in detail. The major noise is not upper level dephasing but a relatively benign blinking on timescale much larger than radiative recombination. The results strike us as important for single photon generation at a key wavelength for quantum technology: we achieve a perfect match to the wavelength of the Rb D2 transition. In Basel, the results are particularly relevant for our on-going efforts to create a hybrid semiconductor-cold atom quantum memory.
Matthias Löbl, a graduate of RWTH Aachen University, started his PhD today. Matthias will work on semiconductor quantum dots, specifically the hole spin using resonance fluorescence for spin read-out.
Jonas Roch, an EPFL graduate, started his PhD today. Jonas will work on hybrid structures for nano-photonics, initially on optically-active two-dimensional materials.