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Type: doctoralThesis × Start date: 2020 × End date: 2022 ×

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    Binomische Kommunikation : Aktivierung des Selbsterneuerungspotentials am Beispiel wissenschaftlicher Bibliotheken
    (Frankfurt am Main [u.a.] : Peter Lang, 2003) Huesmann, Anna-Maria; Geißler, Harald; Petersen, Jendrik
    Die Abhandlung untersucht theoretisch und empirisch Einflußbereiche, die sich auf den nachhaltigen Erfolg von Veränderungsprozessen in wissenschaftlichen Bibliotheken, als Dienstleistungsunternehmen des öffentlichen Sektors, auswirken können. Fokussiert wird der strategische Erfolgsfaktor zwischenmenschliche Kommunikation. Isoliert werden einige, aus der Qualität der interpersonalen Kompetenz resultierende, kommunikative Barrieren. Aufbauend auf die hergeleiteten Konsequenzen wird abschließend die andragogische Methode der Binomischen Kommunikation entwickelt und vorgestellt. Hierbei handelt es sich um eine dialogische, verständigungsorientierte, auf gründlichen Reflexionen und überprüftem Wissen basierte Vorgehensweise, die das Selbsterneuerungspotential der Mitarbeiter aktiviert und damit die permanente und nachhaltig wirkende Innovation des Dienstleistungsunternehmens sichert.
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    Terahertz quantum-cascade lasers for spectroscopic applications
    (Berlin : Technische Universität Berlin, 2018) Röben, Benjamin Malte; Grahn, Holger T.
    Terahertz (THz) quantum-cascade lasers (QCLs) are unipolar semiconductor heterostructure lasers that emit in the far-infrared spectral range. They are very attractive radiation sources for spectroscopy, since they are very compact and exhibit typical output powers of severalmWas well as linewidths in the MHz to kHz range. This thesis presents the development of methods to tailor the emission characteristics of THz QCLs and employ them for spectroscopy with highest resolution and sensitivity. In many cases, these spectroscopic applications require that the far-field distribution of the THz QCLs exhibits only a single lobe. However, multiple lobes in the far-field distribution of THz QCLs were experimentally observed, which were unambiguously attributed to the typically employed mounting geometry and to the cryogenic operation environment such as the optical window. Based on these results, a method to obtain a single-lobed far-field distribution is demonstrated. A critical requirement to employ a THz QCL for high-resolution spectroscopy of a single absorption or emission line is the precise control of its emission frequency. This long-standing problem is solved by a newly developed technique relying on the mechanical polishing of the front facet. A QCL fabricated in this manner allows for spectroscopy at a maximal resolution in the MHz to kHz range, but its accessible bandwidth is usually limited to a few GHz. In contrast, a newly developed method to utilize QCLs as sources for THz Fourier transform spectrometers enables highly sensitive spectroscopy over a significantly larger bandwidth of at least 72 GHz with a maximal resolution of typically 100 MHz. The application of QCLs as sources for THz Fourier transform spectroscopy leads to a signal-to-noise ratio and dynamic range that is substantially increased by a factor of 10 to 100 as compared to conventional sources. The results presented in this thesis pave the way to routinely employ THz QCLs for spectroscopic applications in the near future.