Filters

2019 - 20202

More filters

20212
Reset filters

Settings

Subject: Optical fibers × WGL Institute: MBI ×

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Relativistic-intensity near-single-cycle light waveforms at kHz repetition rate
    (London : Nature Publishing Group, 2020) Ouillé, Marie; Vernier, Aline; Böhle, Frederik; Bocoum, Maïmouna; Jullien, Aurélie; Lozano, Magali; Rousseau, Jean-Philippe; Cheng, Zhao; Gustas, Dominykas; Blumenstein, Andreas; Simon, Peter; Haessler, Stefan; Faure, Jérôme; Nagy, Tamas; Lopez-Martens, Rodrigo
    The development of ultra-intense and ultra-short light sources is currently a subject of intense research driven by the discovery of novel phenomena in the realm of relativistic optics, such as the production of ultrafast energetic particle and radiation beams for applications. It has been a long-standing challenge to unite two hitherto distinct classes of light sources: those achieving relativistic intensity and those with pulse durations approaching a single light cycle. While the former class traditionally involves large-scale amplification chains, the latter class places high demand on the spatiotemporal control of the electromagnetic laser field. Here, we present a light source producing waveform-controlled 1.5-cycle pulses with a 719 nm central wavelength that can be focused to relativistic intensity at a 1 kHz repetition rate based on nonlinear post-compression in a long hollow-core fiber. The unique capabilities of this source allow us to observe the first experimental indications of light waveform effects in laser wakefield acceleration of relativistic energy electrons. © 2020, The Author(s).
  • Thumbnail Image
    Item
    Low-loss fiber-to-chip couplers with ultrawide optical bandwidth
    (Melville, NY : AIP Publishing, 2019) Gehring, H.; Blaicher, M.; Hartmann, W.; Varytis, P.; Busch, K.; Wegener, M.; Pernice, W.H.P.
    Providing efficient access from optical fibers to on-chip photonic systems is a key challenge for integrated optics. In general, current solutions allow either narrowband out-of-plane-coupling to a large number of devices or broadband edge-coupling to a limited number of devices. Here we present a hybrid approach using 3D direct laser writing, merging the advantages of both concepts and enabling broadband and low-loss coupling to waveguide devices from the top. In the telecom wavelength regime, we demonstrate a coupling loss of less than -1.8 dB between 1480 nm and 1620 nm. In the wavelength range between 730 nm and 1700 nm, we achieve coupling efficiency well above -8 dB which is sufficient for a range of broadband applications spanning more than an octave. The 3D couplers allow relaxed mechanical alignment with respect to optical fibers, with -1 dB alignment tolerance of about 5 μm in x- and y-directions and -1 dB alignment tolerance in the z-direction of 34 μm. Using automatized alignment, many such couplers can be connected to integrated photonic circuits for rapid prototyping and hybrid integration. © 2019 Author(s).