show Content M. Nissen, B. Doherty, J. Hamperl, J. Kobelke, K. Weber, T. Henkel, M. A. Schmidt, "UV Absorption Spectroscopy in Water-Filled Antiresonant Hollow Core Fibers for Pharmaceutical Detection," Sensors 18, 478-480 (2018)


Due to a worldwide increased use of pharmaceuticals and, in particular, antibiotics, a growing number of these substance residues now contaminate natural water resources and drinking supplies. This triggers a considerable demand for low-cost, high-sensitivity methods for monitoring water quality. Since many biological substances exhibit strong and characteristic absorption features at wavelengths shorter than 300 nm, UV spectroscopy presents a suitable approach for the quantitative identification of such water-contaminating species. However, current UV spectroscopic devices often show limited light-matter interaction lengths, demand sophisticated and bulky experimental infrastructure which is not compatible with microfluidics, and leave large fractions of the sample analyte unused. Here, we introduce the concept of UV spectroscopy in liquid-filled anti-resonant hollow core fibers, with large core diameters and lengths of approximately 1 m, as a means to overcome such limitations. This extended light-matter interaction length principally improves the concentration detection limit by two orders of magnitude while using almost the entire sample volume—that is three orders of magnitude smaller compared to cuvette based approaches. By integrating the fibers into an optofluidic chip environment and operating within the lowest experimentally feasible transmission band, concentrations of the application-relevant pharmaceutical substances, sulfamethoxazole (SMX) and sodium salicylate (SS), were detectable down to 0.1 µM (26 ppb) and 0.4 µM (64 ppb), respectively, with the potential to reach significantly lower detection limits for further device integration.


show Content M. Chemnitz, R. Scheibinger, Ch. Gaida, M.Gebhardt, F. Stutzki, S. Pumpe, J. Kobelke, A. Tünnermann, J. Limpert, and M. A. Schmidt, "Thermodynamic control of soliton dynamics in liquid-core fibers," Optica 5, 695 (2018).


Liquid-core fibers offer local external control over pulse dispersion due to their strong thermodynamic response, offering a new degree of freedom in accurate soliton steering for reconfigurable nonlinear light generation. Here, we show how to accurately control soliton dynamics and supercontinuum generation in carbon disulfide/silica fibers by temperature and pressure tuning, monitored via the spectral location and the onset energy of non-solitonic radiation. Simulations and phase-matching calculations based on an extended thermodynamic dispersion model of carbon disulfide confirm the experimental results, which allows us to demonstrate the potential of temperature detuning of liquid-core fibers for octave spanning recompressible supercontinuum generation in the near-infrared.


show Content C. Gaida et al., "High-power frequency comb at 2  μm wavelength emitted by a Tm-doped fiber laser system," Opt. Lett. 43, 5178 (2018)


We report on the generation of a high-power frequency comb in the 2 μm wavelength regime featuring high amplitude and phase stability with unprecedented laser parameters, combining 60 W of average power with <30  fs<30  fs pulse duration. The key components of the system are a mode-locked Er:fiber laser, a coherence-preserving nonlinear broadening stage, and a high-power Tm-doped fiber chirped-pulse amplifier with subsequent nonlinear self-compression of the pulses. Phase locking of the system resulted in a phase noise of less than 320 mrad measured within the 10 Hz–30 MHz band and 30 mrad in the band from 10 Hz to 1 MHz.


show Content M. Heck, S. Nolte, A. Tünnermann, R. Vallée, and M. Bernier, "Femtosecond-written long-period gratings in fluoride fibers," Opt. Lett. 43, 1994 (2018).


Long-period gratings induced in fluoride glass fibers using femtosecond laser pulses at 800 nm are, to the best of our knowledge, demonstrated for the first time. By means of tightly confined ultrashort laser pulses, smooth periodic lines of refractive index changes are induced along the fiber core. Taking advantage of heat accumulation effects in the focal volume, attenuation peaks down to 24  dB−24  dB , with sharp and predictable spectral resonances, were obtained. Thermal annealing of the grating up to 250°C yielded a significant reduction of the induced refractive index change. The gratings could find applications in various integrated mid-infrared optical devices, such as optical notch filters in fiber amplifiers.


show Content A. Alberucci, C. P. Jisha, and S. Nolte, "Photonic potential for TM waves," Opt. Lett. 43, 4949 (2018).


We discuss the effective photonic potential for TM waves in inhomogeneous isotropic media. The model provides an easy and intuitive comprehension of form birefringence, paving the way for a new approach on the design of graded-index optical waveguides on nanometric scales. We investigate the application to nanophotonic devices, including integrated nanoscale wave plates and slot waveguides.


show Content T. A. Goebel et al., "Realization of aperiodic fiber Bragg gratings with ultrashort laser pulses and the line-by-line technique," Opt. Lett. 43, 3794 (2018).


We demonstrate the fabrication of aperiodic fiber Bragg gratings (AFBGs) for their application as filter elements. Direct inscription was performed by focusing ultrashort laser pulses with an oil-immersion objective into the fiber core and utilizing the line-by-line technique for flexible period adaptation. The AFBGs inscribed allow for the suppression of 10 lines in a single grating and are in excellent agreement with simulations based on the specific design. Applications in astronomy for the suppression of hydroxyl emission lines are discussed.


show Content K. Bergner, B. Seyfarth, K. A. Lammers, T. Ullsperger, S. Döring, M. Heinrich, M. Kumkar, D. Flamm, A. Tünnermann, and S. Nolte, "Spatio-temporal analysis of glass volume processing using ultrashort laser pulses," Appl. Opt. 57, 4618 (2018).


Ultrashort laser pulses allow for the in-volume processing of glass through non-linear absorption, resulting in permanent material changes and the generation of internal stress. Across the manifold potential applications of this technology, process optimization requires a detailed understanding of the laser–matter interaction. Of particular relevance are the deposition of energy inside the material and the subsequent relaxation processes. In this paper, we investigate the spatio-temporal evolution of free carriers, energy transfer, and the resulting permanent modifications in the volume of glass during and after exposure to femtosecond and picosecond pulses. For this purpose, we employ time-resolved microscopy in order to obtain shadowgraphic and interferometric images that allow relating the transient distributions to the refractive index change profile. Whereas the plasma generation time is given by the pulse duration, the thermal dynamics occur over several microseconds. Among the most notable features is the emergence of a pressure wave due to the sudden increase of temperature and pressure within the interaction volume. We show how the structure of the modifications, including material disruptions as well as local defects, can be directly influenced by a judicious choice of pulse duration, pulse energy, and focus geometry.


show Content G. Matthäus, H. Kämmer, K. A. Lammers, C. Vetter, W. Watanabe, and S. Nolte, "Inscription of silicon waveguides using picosecond pulses," Opt. Express 26, 24089 (2018).


Direct writing of single-mode waveguides into crystalline silicon using ps laser pulses is presented. The embedded structures were fabricated by moving the focal position along the beam axis with the help of a long distance microscope objective. In situ monitoring during inscription was performed to analyze the processing dynamics. The waveguide generation is based on pronounced multi-pulse interaction at moderate pulse energies around 100 nJ. All samples were characterized in terms of mode field distribution and damping losses. Calculations indicate an induced refractive index change in the range of 10−3 to 10−2. Moreover, a Y-splitter was realized to demonstrate the potential of this process.


show Content J. F. Löchner et al., "Polarization-Dependent Second Harmonic Diffraction from Resonant GaAs Metasurfaces," ACS Photonics, 5, 1786 (2018).


Resonant semiconductor metasurfaces are an emerging versatile platform for nonlinear photonics. In this work, we investigate second-harmonic generation from metasurfaces consisting of two-dimensional square arrays of gallium arsenide nanocylinders as a function of the polarization of the fundamental wave. To this end, we perform nonlinear second harmonic microscopy, where the pump wavelength is tuned to the resonances of the metasurfaces. Furthermore, imaging the generated nonlinear signal in Fourier space allows us to analyze the spatial properties of the generated second harmonic. Our experiments reveal that the second harmonic is predominantly emitted into the first diffraction orders of the periodic arrangements, and that its intensity varies with the polarization angle of the fundamental wave. While this can be expected from the structure of the GaAs nonlinear tensor, the characteristics of this variation itself are found to depend on the pump wavelength. Interestingly, we show that the metasurface can reverse the polarization dependence of the second harmonic with respect to an unstructured GaAs wafer. These general observations are confirmed by numerical simulations using a simplified model for the metasurface. Our results provide valuable input for the development of metasurface-based classical and quantum light sources based on parametric processes.


show Content A. Alberucci, C. P. Jisha, S. Bolis, J. Beeckman and S. Nolte, "Interplay between multiple scattering and optical nonlinearity in liquid crystals," Opt. Lett. 43, 3461 (2018).


We discuss the role played by time-dependent scattering on light propagation in liquid crystals. In the linear regime, the effects of the molecular disorder accumulate in propagation, yielding a monotonic decrease in the beam spatial coherence. In the nonlinear case, despite the disorder-imposed Brownian-like motion to the self-guided waves, self-focusing increases the spatial coherence of the beam by inducing spatial localization. Eventually, a strong enhancement in the beam oscillations occurs when power is strong enough to induce self-steering, i.e., in the non-perturbative regime.


show Content A. Alberucci, R. Barboza, C. P. Jisha, and S. Nolte, "Temporal dynamics of light-written waveguides in unbiased liquid crystals," J. Opt. Soc. Am. B 35, 1878 (2018).


The control of light by light is one of the main aims in modern photonics. In this context, a fundamental cornerstone is the realization of light-written waveguides in real time, resulting in all-optical reconfigurability of communication networks. Light-written waveguides are often associated with spatial solitons, that is, non-diffracting waves due to a nonlinear self-focusing effect in the harmonic regime. From an applicative point of view, it is important to establish the temporal dynamics for the formation of such light-written guides. Here, we investigate theoretically the temporal dynamics in nematic liquid crystals, a material where spatial solitons can be induced using continuous wave lasers with a few milliwatts of power. We fully address the role of the spatial walk-off and the longitudinal nonlocality in the waveguide formation. We show that for powers large enough to induce light self-steering the beam undergoes several fluctuations before reaching the stationary regime, in turn leading to a much longer formation time for the light-written waveguide.


show Content K. Schaarschmidt, S. Weidlich, D. Reul, and M. A. Schmidt, "Bending losses and modal properties of nano-bore optical fibers," Opt. Lett. 43, 4192 (2018).


The nano-bore optical fiber geometry represents a new waveguide platform that uniquely allows studying the interaction of low-index fluids and light inside the core of an optical fiber while maintaining total internal reflection as a light guidance mechanism. Here, we have analyzed several application-relevant properties of this novel geometry experimentally and from the simulation perspective, including the analysis of the power fraction inside the bore, the determination of radius-dependent cutoffs, and the identification of single-mode operation domains. The obtained results will pave the way for new application of fiber optics in fields such as optofluidics, nonlinear light generation, and bioanalytics.


show Content S. Jiang, K. Schaarschmidt, S. Weidlich, and M.A. Schmidt, "Fiber-Integrated Absorption Spectroscopy Using Liquid-Filled Nanobore Optical Fibers," J.Light. Technol. 36, 3970 (2018).


Absorption spectroscopy represents one highly relevant approach in current analytics to noninvasively characterize liquid analytes. Here we present the concept of waveguide-integrated absorption spectroscopy via nanobore optical fibers. Using a liquid-filled nanochannel inside the core of a microstructured step-index fiber, the spectroscopic characteristics of liquid analytes located inside the nanochannel are imprinted onto the propagating mode via its evanescent fields, allowing to conduct absorption spectroscopic experiments at extremely small sample volume levels. We reveal the limits of this spectroscopic approach by analyzing the dependence of the power fraction inside the bore on the fiber parameters and experimentally demonstrate its capabilities by (i) using the cut-back technique using an optofluidic mount and (ii) fully encapsulating a highly doped dye solution inside the nanobore fiber. Based on its high degree of integration and the straightforward handling capabilities, application of the nanobore fiber based absorption spectroscopy concept can be anticipated in fields such as bioanalytics, analytical chemistry and environmental science.


show Content T. Grigorova, R. Sollapur, N. Jayakumar, A. Hoffmann, A. Hartung, A. Schwuchow, J. Bierlich, J. Kobelke, M. A. Schmidt, and C. Spielmann, "Measurement of the Dispersion of an Antiresonant Hollow Core Fiber," IEEE Photon. J. 10(4), 1-6 (2018).


Due to unique properties, antiresonant hollow core fibers have found widespread use in various fields of science and application. Particular regarding applications that involve ultrashort pulses, precise knowledge of group velocity dispersion is essential to understand the underlying physics and to optimize device performance. Here we report on the successful measurement of the spectral distribution of the group velocity dispersion of the fundamental mode of an antiresonant hollow core fiber in close proximity to and away from a strong strand resonance. The results show the variations of the hundreds of fs 2 /cm near the resonance region, whereas the dispersion is identical to that of a perfect cylindrical waveguide away from the resonance in accordance with a literature. An additional zero dispersion wavelength that is not present in the case of a capillary was experimentally verified. The possibility to tune dispersion via strand resonances opens up a novel pathway towards engineering pulse dispersion, with applications in fields such as nonlinear science and pulse propagation management.


show Content N. Jayakumar, R. Sollapur, A. Hoffmann, T. Grigorova, A. Hartung, A. Schwuchow, J. Bierlich, J. Kobelke, M. A. Schmidt, and C. Spielmann, "Polarization evolution in antiresonant hollow core fiber," Appl. Opt. 57, 8529 (2018).


We experimentally demonstrate that the ellipticity of light exiting antiresonant hollow core fibers is a function of the input polarization which manifests as ellipticity varying with the azimuthal periodicity of the cornered core.


show Content C. Jauregui, C. Stihler, A. Tünnermann, and J. Limpert, "Pump-modulation-induced beam stabilization in high-power fiber laser systems above the mode instability threshold," Opt. Express 26, 10691 (2018)


A new way of stabilizing the output beam of a fiber laser system operating above the mode instability threshold is described and the first proof-of-principle experimental results are presented. This technique, which relies on a modulation of the pump power, works by washing the thermally-induced refractive index grating out, which weakens the coupling efficiency between transverse modes. One of the main advantages of this simple, yet powerful, approach is that it can be easily incorporated in already existing fiber laser systems since it does not require any additional optical elements. Using this beam stabilization strategy, a significant pointing stability and beam quality improvement has been demonstrated up to an average power of ~600W, which is a factor of 2 above the mode instability threshold.


show Content C. Stihler, C. Jauregui, A. Tünnermann, and J. Limpert, "Modal energy transfer by thermally induced refractive index gratings in Yb-doped fibers," Light Sci. Appl. 7, 59 (2018).


Thermally induced refractive index gratings in Yb-doped fibers lead to transverse mode instability (TMI) above an average power threshold, which represents a severe problem for many applications. To obtain a deeper understanding of TMI, the evolution of the strength of the thermally induced refractive index grating with the average output power in a fiber amplifier is experimentally investigated for the first time. This investigation is performed by introducing a phase shift between the refractive index grating and modal interference pattern, which is obtained by applying a pump power variation to the fiber amplifier. It is demonstrated that the refractive index grating is sufficiently strong to enable modal energy coupling at powers that are significantly below the TMI threshold if the induced phase shift is sufficiently large. The experiments indicate that at higher powers, the refractive index grating becomes more sensitive to such phase shifts, which will ultimately trigger TMI. Furthermore, the experimental results demonstrate beam cleaning above the TMI threshold via the introduction of a positive phase shift. This finding paves the way for the development of a new class of mitigation strategies for TMI that are based on controlling the phase shift between the thermally induced refractive index grating and modal interference pattern.


show Content C. Stihler, C. Jauregui, A. Tünnermann, and J. Limpert, "Phase-shift evolution between the modal interference pattern and the thermally-induced refractive index grating in high-power fiber laser systems," Opt. Express 26, 19489 (2018).


A phase shift between the modal interference pattern and the thermally-induced refractive index grating is most likely the ultimate trigger for the damaging effect of transverse mode instabilities (TMI) in high-power fiber laser systems. By using comprehensive simulations, the creation and evolution of a thermally-induced phase shift is explained and illustrated in detail. It is shown that such a phase shift can be induced by a variation of the pump power. The gained knowledge about the generation and evolution of the phase shift will allow for the development of new mitigation strategies for TMI.


show Content M. Chemnitz, C. Gaida, M. Gebhardt, F. Stutzki, J. Kobelke, A. Tünnermann, J. Limpert, and M. A. Schmidt, "Carbon Chloride-core fibers for soliton mediated supercontinuum generation," Opt. Express 26, 3221 (2018).


We report on soliton-fission mediated infrared supercontinuum generation in liquid-core step-index fibers using highly transparent carbon chlorides (CCl4, C2Cl4). By developing models for the refractive index dispersions and nonlinear response functions, dispersion engineering and pumping with an ultrafast thulium fiber laser (300 fs) at 1.92 μm, distinct soliton fission and dispersive wave generation was observed, particularly in the case of tetrachloroethylene (C2Cl4). The measured results match simulations of both the generalized and a hybrid nonlinear Schrödinger equation, with the latter resembling the characteristics of non-instantaneous medium via a static potential term and representing a simulation tool with substantially reduced complexity. We show that C2Cl4 has the potential for observing non-instantaneous soliton dynamics along meters of liquid-core fiber opening a feasible route for directly observing hybrid soliton dynamics.


show Content T. Heuermann, C. Gaida, M. Gebhardt, and J. Limpert, "Thulium-doped nonlinear fiber amplifier delivering 50  fs pulses at 20  W of average power," Opt. Lett. 43, 4441 (2018).


In this Letter, we present an optimized nonlinear amplification scheme in the 2 μm wavelength region. This laser source delivers 50 fs pulses at an 80 MHz repetition rate with exceptional temporal pulse quality and 20 W of average output power. According to predictions from numerical simulations, it is experimentally confirmed that dispersion management is crucial to prevent the growth of side pulses and an increase of the energy content in a temporal pedestal surrounding the self-compressed pulse. Based on these results, we discuss guidelines to ensure high temporal pulse quality from nonlinear femtosecond fiber amplifiers in the anomalous dispersion regime.


show Content C. Gaida, M. Gebhardt, T. Heuermann, F. Stutzki, C. Jauregui, and J. Limpert, "Ultrafast thulium fiber laser system emitting more than 1  kW of average power," Opt. Lett. 43, 5853 (2018).


In this Letter, we report on the generation of 1060 W average power from an ultrafast thulium-doped fiber chirped pulse amplification system. After compression, the pulse energy of 13.2 μJ with a pulse duration of 265 fs at an 80 MHz pulse repetition rate results in a peak power of 50 MW spectrally centered at 1960 nm. Even though the average heat-load in the fiber core is as high as 98 W/m, we confirm the diffraction-limited beam quality of the compressed output. Furthermore, the evolution of the relative intensity noise with increasing average output power has been measured to verify the absence of transversal mode instabilities. This system represents a new average power record for thulium-doped fiber lasers (1150 W uncompressed) and ultrashort pulse fiber lasers with diffraction-limited beam quality, in general, even considering single-channel ytterbium-doped fiber amplifiers.


show Content T. Lühder, T. Wieduwilt, H. Schneidewind, and M. A. Schmidt, "Electric current-driven spectral tunability of surface plasmon polaritons in gold coated tapered fibers," AIP Adv. 8, 9 (2018).


Here we introduce the concept of electrically tuning surface plasmon polaritons using current-driven heat dissipation, allowing controlling plasmonic properties via a straightforward-to-access quantity. The key idea is based on an electrical current flowing through the plasmonic layer, changing plasmon dispersion and phase-matching condition via a temperature-imposed modification of the refractive index of one of the dielectric media involved. This scheme was experimentally demonstrated on the example of an electrically connected plasmonic fiber taper that has sensitivities >50000 nm/RIU. By applying a current, dissipative heat generated inside metal film heats the surrounding liquid, reducing its refractive index correspondingly and thus modifying the phase-matching condition to the fundamental taper mode. We observed spectral shifts of the plasmonic resonance up to 300 nm towards shorter wavelength by an electrical power of ≤ 80 mW, clearly showing that our concept is important for applications that demand precise real-time and external control on plasmonic dispersion and resonance wavelengths.


show Content R. Klas, A. Kirsche, M. Tschernajew, J. Rothhardt, and J. Limpert, "Annular beam driven high harmonic generation for high flux coherent XUV and soft X-ray radiation," Opt. Express 26, 19318 (2018).


Separation of the high average power driving laser beam from the generated XUV to soft-X-ray radiation poses great challenges in collinear HHG setups due to the losses and the limited power handling capabilities of the typically used separating optics. This paper demonstrates the potential of driving HHG with annular beams, which allow for a straightforward and power scalable separation via a simple pinhole, resulting in a measured driving laser suppression of 5⋅10−3. The approach is characterized by an enormous flexibility as it can be applied to a broad range of input parameters and generated photon energies. Phase matching aspects are analyzed in detail and an HHG conversion efficiency that is only 27% lower than using a Gaussian beam under identical conditions is demonstrated, revealing the viability of the annular beam approach for high flux coherent short-wavelength sources and high average power driving lasers.


show Content K. Bergner, M. Müller, R. Klas, J. Limpert, S. Nolte, and A. Tünnerman, "Scaling ultrashort laser pulse induced glass modifications for cleaving applications," Appl. Opt. 57, 5941 (2018).


Ultrashort laser pulses allow for in-volume processing of glass through non-linear absorption. This results in permanent material changes, largely independent of the processed glass, and it is of particular relevance for cleaving applications. In this paper, a laser with a wavelength of 1030 nm, pulse duration of 19 ps, repetition rate of 10 kHz, and burst regime consisting of either four or eight pulses, with an intra-burst pulse separation of 12.5 ns, is used. Subsequently, a Gaussian–Bessel focal line is generated in a fused silica substrate with the aid of an axicon configuration. We show how the structure of the modifications, including the length of material disruptions and affected zones, can be directly influenced by a reasonable choice of focus geometry, pulse energy, and burst regime. We achieve single-shot modifications with 2 μm in diameter and 7.6 mm in length, exceeding an aspect ratio of 1:3800. Furthermore, a maximum length of 10.8 mm could be achieved with a single shot.


show Content G. K. Tadesse et al., "High resolution XUV Fourier transform holography on a table top," Sci. Rep. 8, 8677 (2018).


Today, coherent imaging techniques provide the highest resolution in the extreme ultraviolet (XUV) and X-ray regions. Fourier transform holography (FTH) is particularly unique, providing robust and straightforward image reconstruction at the same time. Here, we combine two important advances: First, our experiment is based on a table-top light source which is compact, scalable and highly accessible. Second, we demonstrate the highest resolution ever achieved with FTH at any light source (34 nm) by utilizing a high photon flux source and cutting-edge nanofabrication technology. The performance, versatility and reliability of our approach allows imaging of complex wavelength-scale structures, including wave guiding effects within these structures, and resolving embedded nanoscale features, which are invisible for electron microscopes. Our work represents an important step towards real-world applications and a broad use of XUV imaging in many areas of science and technology. Even nanoscale studies of ultra-fast dynamics are within reach.


show Content M. Wimmer and U. Peschel, "Observation of Time Reversed Light Propagation by an Exchange of Eigenstates," Sci. Rep. 8, 2125 (2018).


As time flow dictates all evolution, its effective reversal is a topic of active research in a broad range of disciplines, including acoustics, hydrodynamics and optics. This multifarious set of environments is reflected by a great diversity of approaches to observe various echoes of wave functions. Here, we experimentally demonstrate time reversal of a pulse sequence propagating through a photonic mesh lattice realized by two coupled loops of telecommunication fibres. Our system features a symmetric band structure, which allows for almost perfect reversal of its evolution by exchanging the population between two opposing bands. The protocol applied is based on a non-adiabatic and instantaneous exchange of eigenstates resulting in highly efficient time reversal of a pulse chain.


show Content Presentations at conferences


  • Ni. Jayakumar, R. Sollapur, A. Hoffmann, T. Grigorova, A. Hartung, A. Schwuchow, J. Bierlich, J. Kobelke, M. A. Schmidt, C. Spielmann, “Polarization Evolution in  Antiresonant Hollow-Core Fibers”, Conference on Lasers and Electro-Optics, 2018.

  • Rudrakant Sollapur, Bruno Schmidt, Philippe Lassonde, Shoufei Gao, Yingying Wang, Pu Wang, François Légaré, Christian Spielmann, "2.5 Cycle Pulses Obtained With Self Compression At 1.8 μm In Antiresonant Waveguides ", Conference on Lasers and Electro-Optics, 2018.
  • R. Sollapur, D. Kartashov, M. Zürch, B. E. Schmidt, A. Hoffmann, T.Grigorova, A. Hartung, A. Schwuchow, J. Bierlich, J. Kobelke, M Chemnitz, S. Gao, Y. Wang, P. Wang, P. Lassonde, M A. Schmidt, F. Légaré, C. Spielmann / „Supercontinuum and few cycle pulse generation in antiresonant hollow core fibers“: Photonics North, Montreal 2018

  • Vittoria Schuster, Robert Klas, Vinzenz Hilbert, Maxim Tschernajew, Jan Rothhardt, Jens Limpert, Birgitta Bernhard / „Twin Pulse High Harmonic Generation for XUV Fourier Transform Spectroscopy”: Photonics North, Montreal 2018

  • Kim Lammers, Stefan Nolte / „Embedded Nanogratings for Polarization Control in Femtosecond Laser Direct Written Waveguides”: Photonics North, Montreal 2018

  • Maximilian Heck, Réal Vallée, Andreas Tünnermann, Stefan Nolte, Martin Bernier / „Femtosecond-written long period gratings in fluoride fibers”: Photonics North, Montreal 2018

  • Brenda Doherty, Markus A. Schmidt / „Plasmonic nanoparticle-functionalised microstructured optical fibres for biosensing-An optofluidic sensing platform”: Photonics North, Montreal 2018

  • Alessandro Alberucci, Stefan Nolte / „Photonic potential for TM waves”: Photonics North, Montreal 2018

  • Friedrich G. Fröbel, V. Engel, Stefanie Gräfe / „Spin-Dependent Asymmetries in the Photoelectron Momentum Distributions in Single-Photon Double Ionization”: Photonics North, Montreal 2018


  • Christoph Stihler, Cesar Jauregui , Andreas Tünnermann, Jens Limpert  / „Thermally-induced refractive index gratings enabling modal energy transfer in Yb-doped fibers”: Photonics North, Montreal 2018

  • E. Shestaev, D. Hoff, S. Hädrich, F. Just, T. Eidam, M. Sayler, A. Drozdy, P. Jójárt, A. Szabó, Z. Várallyay, K. Osvay, G.G. Paulus, A. Tünnermann, J. Limpert / „Towards Highly Carrier-Envelope Stable High-Power Few-Cycle Fiber Lasers”: Photonics North, Montreal 2018

  • T. Lühder, T. Wieduwilt, H. Schneidewind, M. A. Schmidt / „Electrically induced tunability  of surface plasmon polaritons in gold coated tapered fibers”: Photonics North, Montreal 2018

  • A.L.M. Muniz, M.Wimmer, A.Bisianov, D.N. Christodoulides, R.Morandotti, U. Peschel / „ Nonlinear Wave Collapse at mW-Power”: Photonics North, Montreal 2018

  • A.L.M. Muniz, M.Wimmer, A.Bisianov, D.N. Christodoulides, R.Morandotti, U. Peschel / „ Nonlinear Wave Collapse at mW-Power”: Photonics North, Montreal 2018

  • Arstan Bisianov, Mark Kremer, Martin Wimmer, Ulf Peschel / „Experiments on Nonlinearity-Driven Excitation of Topological and Trivial states”: Photonics North, Montreal 2018

  • Kay Schaarschmidt, Markus A. Schmidt / „Higher-Order Mode Third Harmonic Generation in Liquid-Core-Optical-Fiber using ultrafast pulses”: Photonics North, Montreal 2018