Einladung zum Promotionsvortrag von Herrn Pierre Türschmann:
„Coherent Coupling of Single Organic Dye Molecules to Optical Nanoguides“
Nanoscopic sources of photons, switches, and memories are in high demand as building blocks for quantum optical networks. Equally important are solutions for efficient “wiring” of these elements. An attractive approach to address these issues is to couple solid-state quantum emitters to a one-dimensional subwavelength waveguide (nanoguide) that acts as an optical wire or bus. We developed a scalable light-matter interface by coupling single organic dye molecules to dielectric nanoguides. Their small effective mode area gives rise to substantial single-emitter coupling efficiencies with expected values up to 35%. At superfluid helium temperatures, organic dye molecules can act almost like an ideal two-level system resulting in large scattering cross sections that are necessary for coherent light-matter interaction. By combining high-resolution microscopy with fluorescence excitation and resonance fluorescence spectroscopy, we study the coupled nanoguide-emitter system. We show that the inherent nonlinearity of single molecules is sufficient to switch and even coherently amplify a weak laser beam in an all-optical fashion. Moreover, we gain local control of the molecular resonance frequencies via the dc Stark effect by applying static electric fields on microelectrodes integrated along our chip-compatible nanoguides. Exploiting this tunability allows us to match the resonance frequencies of two molecules that are coherently coupled to the same waveguide mode. Our presented architecture can be readily extended to more complex geometries and paves the way for the realization of quantum integrated photonic circuits. (Vortrag auf Englisch)
Dem Vortrag schließt sich eine Diskussion von 15 Minuten an. Vortrag und Diskussion sind öffentlich. Diesen Verfahrensteilen folgt ein nicht öffentliches Rigorosum von 45 Minuten.