@article{AmthorWeissenseelFischeretal.2014, author = {Amthor, Matthias and Weißenseel, Sebastian and Fischer, Julian and Kamp, Martin and Schneider, Christian and H{\"o}fling, Sven}, title = {Electro-optical switching between polariton and cavity lasing in an InGaAs quantum well microcavity}, doi = {10.1364/OE.22.031146}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111130}, year = {2014}, abstract = {We report on the condensation of microcavity exciton polaritons under optical excitation in a microcavity with four embedded InGaAs quantum wells. The polariton laser is characterized by a distinct nonlinearity in the input-output-characteristics, which is accompanied by a drop of the emission linewidth indicating temporal coherence and a characteristic persisting emission blueshift with increased particle density. The temporal coherence of the device at threshold is underlined by a characteristic drop of the second order coherence function to a value close to 1. Furthermore an external electric field is used to switch between polariton regime, polariton condensate and photon lasing.}, language = {en} } @article{BrixnerPawłowskaGoetzetal.2014, author = {Brixner, Tobias and Pawłowska, Monika and Goetz, Sebastian and Dreher, Christian and Wurdack, Matthias and Krauss, Enno and Razinskas, Gary and Geisler, Peter and Hecht, Bert}, title = {Shaping and spatiotemporal characterization of sub-10-fs pulses focused by a high-NA objective}, doi = {10.1364/OE.22.031496}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111120}, year = {2014}, abstract = {We describe a setup consisting of a 4 f pulse shaper and a microscope with a high-NA objective lens and discuss the spects most relevant for an undistorted spatiotemporal profile of the focused beam. We demonstrate shaper-assisted pulse compression in focus to a sub-10-fs duration using phase-resolved interferometric spectral modulation (PRISM). We introduce a nanostructure-based method for sub-diffraction spatiotemporal characterization of strongly focused pulses. The distortions caused by optical aberrations and space-time coupling from the shaper can be reduced by careful setup design and alignment to about 10 nm in space and 1 fs in time.}, language = {en} }