@article{23481, abstract = {{A one-dimensional semiconductor nanostructure is locally excited through a metal aperture. It is shown that the electron density can be coherently localized at desired spatial and temporal positions by using nontrivially shaped laser pulses. To obtain the optimized laser field, Bloch equations for a tight-binding model system are solved together with a genetic pulse-shaping algorithm. Full three-dimensional finite-difference time-domain (FDTD) simulations of the Maxwell–Bloch equations confirm the predicted coherent spatiotemporal control.}}, author = {{Reichelt, Matthias and Meier, Torsten}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, number = {{19}}, pages = {{2900--2902}}, title = {{{Shaping the spatiotemporal dynamics of the electron density in a hybrid metal-semiconductor nanostructure}}}, doi = {{10.1364/ol.34.002900}}, volume = {{34}}, year = {{2009}}, } @inproceedings{4184, abstract = {{We have experimentally investigated injection currents generated by all-optical excitation of GaAs/AlGaAs quantum wells excited with 130 fs optical pulses. The currents have been detected via free-space THz experiments at room temperature. Our experiments prove that Coulomb effects strongly influence injection currents. This becomes most prominently visible when exciting light-hole exciton transitions. At this photon energy we observe a pronounced phase shift of the current transients which is due to oppositely oriented heavy-hole and light-hole type contributions. We are currently developing a microscopic theory based on a 14×14 k.p model in combination with the semiconductor Bloch equations to describe the observed features quantitatively. The combined theoretical and experimental approach will allow us to analyze the influence of the bandstructure and interaction effects on the injection current amplitude and current dynamics.}}, author = {{Bieler, M. and Pierz, K. and Siegner, U. and Dawson, P. and Duc, H. T. and Förstner, Jens and Meier, Torsten}}, booktitle = {{Ultrafast Phenomena in Semiconductors and Nanostructure Materials XIII}}, editor = {{Tsen, Kong-Thon and Song, Jin-Joo and Betz, Markus and Elezzabi, Abdulhakem Y.}}, keywords = {{tet_topic_qw}}, location = {{San Jose (California / USA)}}, pages = {{721404--721404--13}}, publisher = {{SPIE}}, title = {{{Generation of injection currents in (110)-oriented GaAs quantum wells: experimental observation and development of a microscopic theory}}}, doi = {{10.1117/12.811841}}, volume = {{7214}}, year = {{2009}}, } @inproceedings{44104, abstract = {{The paper presents a theoretical analysis of the nonlinear THz response from the internal transitions of coherent and incoherent excitons based on the formulated microscopic THz theory. Moreover, the response of unexcited semiconductors to extremely intense THz fields is investigated .The intersubband transitions of optically excited quantum wells using linear THz spectroscopy is also studied. The computed differential transmission shows a characteristic Fano-like line shape of the intersubband resonance. The pure intersubband contribution is given by a simple Lorentzian. Applying the microscopic theory, the Fano features of the total response can be attributed to the phase-sensitive superposition of the intersubband transitions and the ponderomotive contribution. These results are in excellent agreement with recent experiments.}}, author = {{Meier, Torsten and Koch, S.W. and Kira, M. and Steiner, J.T. and Golde, D.}}, booktitle = {{ CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference}}, isbn = {{978-1-4244-4079-5}}, location = {{Munich, Germany}}, publisher = {{IEEE}}, title = {{{Microscopic theory of the linear and nonlinear Terahertz response of semiconductors}}}, doi = {{10.1109/CLEOE-EQEC.2009.5192555}}, year = {{2009}}, } @inproceedings{44105, abstract = {{By combining coherent control schemes and photoelectron spectroscopy it is possible to generate ultrafast current pulses at surfaces and in solids and to detect their decay directly in momentum space with femtosecond time resolution.}}, author = {{Meier, Torsten and Koch, S.W. and Rohleder, M. and Gudde, J. and Hofer, U.}}, booktitle = {{Conference on Lasers and Electro-Optics and 2009 Conference on Quantum electronics and Laser Science Conference}}, issn = {{2160-9004}}, location = {{Baltimore, MD, USA}}, pages = {{1--2}}, publisher = {{IEEE}}, title = {{{Ultrafast coherent photoelectron emission effects and their application for time-domain studies of current transport}}}, doi = {{10.1364/IQEC.2009.IThI5}}, year = {{2009}}, } @article{24983, abstract = {{The recently developed two-dimensional Fourier-Transform-Spectroscopy (2DFTS) in the optical regime has been established as an elegant experiment, which has manifold of applications in the investigation of semiconductor nanostructures. Here we focus on the real and imaginary part 2DFT spectra. As predicted recently, using rephasing and non-rephasing modes, we are able to determine the homogeneous and inhomogeneous broadenings of coupled excitonic resonances even for weak disorder where photon-echo data are not useful. Computed real and imaginary parts of the 2DFTS for rephasing and non-rephasing modes are compared with experimental data of a GaAs quantum well. It is demonstrated, that phase sensitive data for the rephasing and non-rephasing modes are able to accurately provide the disorder induced broadening in a complex coupled system for each transition separately. }}, author = {{Kuznetsova, Irina and Thomas, Peter and Meier, Torsten and Zhang, Tianhao and Cundiff, Steven T.}}, issn = {{1610-1634}}, journal = {{physica status solidi (c)}}, number = {{2}}, pages = {{445--448}}, publisher = {{WILEY‐VCH Verlag}}, title = {{{Determination of homogeneous and inhomogeneous broadenings of quantum-well excitons by 2DFTS: An experiment-theory comparison}}}, doi = {{10.1002/pssc.200880302}}, volume = {{6}}, year = {{2009}}, } @article{24982, abstract = {{A microscopic analysis of the emitted radiation of a semiconductor nanostructure after excitation with an extremely intense ultrashort laser pulse is presented. It is shown that the extreme nonlinear optical response is not sufficiently described by pure interband transitions but one has to include intraband effects as well. Numerical solutions of extended Bloch equations that include the coupled inter- and intraband dynamics are presented. For large excitation intensities, the intraband effects strongly modify the polarization dynamics and lead to a strong enhancement of high-harmonic generation compared to pure interband dynamics.}}, author = {{Golde, Daniel and Meier, Torsten and Koch, Stephan W.}}, issn = {{1610-1634}}, journal = {{physica status solidi (c)}}, number = {{2}}, pages = {{420--423}}, publisher = {{WILEY‐VCH Verlag}}, title = {{{Microscopic analysis of high-harmonic generation in semiconductor nanostructures}}}, doi = {{10.1002/pssc.200880309}}, volume = {{6}}, year = {{2009}}, } @article{44106, author = {{Meier, Torsten and Michler, Peter}}, journal = {{physica status solidi c}}, number = {{2}}, pages = {{379--380}}, publisher = {{WILEY‐VCH Verlag}}, title = {{{Preface}}}, doi = {{10.1002/pssc.200960045}}, volume = {{6}}, year = {{2009}}, } @inproceedings{44178, author = {{Müller, Inez}}, booktitle = {{Autobiographisches Schreiben in der deutschsprachigen Gegenwartsliteratur, Bd. 3: Entwicklungen, Kontexte, Grenzgänge.}}, editor = {{Grote, Michael and Sandberg, Beatrice}}, isbn = {{978-3-89129-951-7}}, location = {{Universität Bergen}}, pages = {{15}}, publisher = {{iudicium Verlag}}, title = {{{Reiseprosa zwischen erlebter und erfundener Erfahrung von Wolfgang Büscher, Hape Kerkeling und Sigrid und Hamster Damm}}}, year = {{2009}}, } @inproceedings{44068, abstract = {{The band structure and wave functions of GaAs quantum wells are computed via k.p band structure theory including anisotropy and spin splitting. Using these results, the process of generating photocurrents by optical excitation is analyzed. Depending on the symmetry of the material, the direction of the laser beam, and the polarization direction of the light field/s, one can coherently generate charge and/or spin photocurrents on ultrashort time scales. The direction, the strength, and the dynamics of these photocurrents are computed and discussed.}}, author = {{Meier, Torsten and Duc, Huynh Thanh and Foerstner, Jens}}, booktitle = {{DPG Spring meeting 2009}}, issn = {{0420-0195}}, location = {{Dresden, Germany}}, number = {{5}}, title = {{{Photo-and spin current generation and dynamics in semiconductor nanostructures}}}, volume = {{44}}, year = {{2009}}, } @book{44550, author = {{Adelmann, Ralf and Frercks, Jan and Heßler, Martina and Hennig, Jochen}}, publisher = {{Transcript}}, title = {{{Datenbilder. Zur digitalen Bildpraxis in den Naturwissenschaften}}}, year = {{2009}}, } @misc{44596, author = {{Adelmann, Ralf}}, booktitle = {{H-Soz-u-Kult}}, title = {{{Rezension zu: Hüppauf, Bernd; Weingart, Peter (Hrsg.): Frosch und Frankenstein. Bilder als Medium der Popularisierung von Wissenschaften. Bielefeld 2009}}}, year = {{2009}}, } @misc{44598, author = {{Adelmann, Ralf and Winkler, Hartmut}}, title = {{{Selbst etwas tun. Handeln und Subjektkonstitution in Computerspielen (Vortrag an der HBK Braunschweig 9.2.2009)}}}, year = {{2009}}, } @inbook{44597, author = {{Adelmann, Ralf}}, booktitle = {{Fasten Your Seatbelt! Bewegtbilder vom Fliegen}}, editor = {{Keilbach, Judith and Schneider, Alexandra}}, pages = {{153–166}}, publisher = {{Lit Verlag}}, title = {{{Geschichten einfliegen? Dynamische Einstellungen in Film und Fernsehen}}}, year = {{2009}}, } @article{44808, author = {{Freitag, Christine}}, journal = {{Seminar – Lehrerbildung und Schule 3/2009}}, pages = {{19--24}}, title = {{{Zurück zur Meisterlehre? Beurteilen lernen und beurteilt werden am Ausbildungsort Schule}}}, year = {{2009}}, } @inbook{44895, author = {{Herzig, Bardo and Grafe, S.}}, booktitle = {{Schule in der digitalen Welt}}, editor = {{Albers, C. and Magenheim, J. and Meister, D.}}, pages = {{67--96}}, publisher = {{VS-Verlag}}, title = {{{Wirkungen digitaler Medien}}}, year = {{2009}}, } @article{44894, author = {{Herzig, Bardo and Aßmann, S. and Altmann, R.}}, journal = {{mathematik lehren. Begriffe klären, Konzepte entwickeln, Schule verändern.152 (2009)}}, pages = {{22--26}}, title = {{{Selbstreguliertes Lernen fördern. }}}, year = {{2009}}, } @book{44893, author = {{Tulodziecki, G. and Herzig, Bardo and Blömeke, S.}}, publisher = {{Klinkhardt Verlag / UTB}}, title = {{{Gestaltung von Unterricht. Eine Einführung in die Didaktik}}}, year = {{2009}}, } @article{44957, author = {{Thar, J. and Brehm, Martin and Seitsonen, A. P. and Kirchner, B.}}, journal = {{J. Phys. Chem. B}}, pages = {{15129--15132}}, title = {{{Unexpected Hydrogen Bond Dynamics in Imidazolium-Based Ionic Liquids}}}, doi = {{10.1021/jp908110j}}, volume = {{113 (46)}}, year = {{2009}}, } @inbook{45020, author = {{Herzig, Bardo and Grafe, S.}}, booktitle = {{Medienbildung in neuen Kulturräumen: Aufgaben, Adressaten, Ansätze}}, editor = {{Bachmair, B.}}, pages = {{187--199}}, publisher = {{Kohlhammer Verlag}}, title = {{{Digitale Medien in Schule und Alltagswelt. Zur Verbindung von formalen und informellen Lernprozessen}}}, year = {{2009}}, } @inbook{45021, author = {{Herzig, Bardo and Aßmann, S.}}, booktitle = {{Handbuch der Erziehungswissenschaft. Band III: Familie, Kindheit, Jugend, Gender, Umwelten}}, editor = {{Mertens, G. and Frost, U. and Böhm, W. and Ladenthin, V.}}, pages = {{893--912}}, publisher = {{Schöningh}}, title = {{{Mediendidaktik}}}, year = {{2009}}, }