A5091488910- Advanced Fiber Laser Technologies
- Metaheuristic Optimization Algorithms Research
- Evolutionary Algorithms and Applications
- Advanced Frequency and Time Standards
- Advanced Multi-Objective Optimization Algorithms
- Photonic and Optical Devices
- Photonic Crystal and Fiber Optics
- Laser-Matter Interactions and Applications
- Advanced X-ray Imaging Techniques
- Scientific Measurement and Uncertainty Evaluation
- Optimization and Search Problems
- Spectroscopy and Laser Applications
- Optical Network Technologies
- Cold Atom Physics and Bose-Einstein Condensates
- Solid State Laser Technologies
- Semiconductor Lasers and Optical Devices
- Reinforcement Learning in Robotics
- Scheduling and Optimization Algorithms
- Advanced Electron Microscopy Techniques and Applications
- Mass Spectrometry Techniques and Applications
- Advanced Surface Polishing Techniques
- Formal Methods in Verification
- Laser-Plasma Interactions and Diagnostics
- Gene Regulatory Network Analysis
- Advanced Fiber Optic Sensors
Vescent Photonics (United States)
2022-2023
SLAC National Accelerator Laboratory
2018-2022
Linac Coherent Light Source
2020-2021
Deutsches Elektronen-Synchrotron DESY
2021
National Institute of Standards and Technology
2016-2020
Max Planck Institute of Quantum Optics
2011-2014
Max Planck Society
2012-2013
TU Dortmund University
1998-2006
University of Wuppertal
2005
To compare the increasing number of optical frequency standards, highly stable signals have to be transferred over continental distances. We demonstrate optical-frequency transfer a 1840-km underground fiber link using single-span stabilization. The low inherent noise introduced by allows us reach short term instabilities expressed as modified Allan deviation 2×10(-15) for gate time τ 1 s reaching 4×10(-19) in just 100 s. find no systematic offset between sent and frequencies within...
Using aluminum-nitride photonic-chip waveguides, we generate optical-frequency-comb supercontinuum spanning from 500 nm to 4000 with a 0.8 nJ seed pulse, and show that the spectrum can be tailored by changing waveguide geometry. Since aluminum nitride exhibits both quadratic cubic nonlinearities, spectra feature simultaneous contributions numerous nonlinear mechanisms: generation, difference-frequency second-harmonic third-harmonic generation. As one application of integrating multiple...
We utilize silicon-nitride waveguides to self-reference a telecom-wavelength fiber frequency comb through supercontinuum generation, using 11.3 mW of optical power incident on the chip. This is approximately 10 times lower than conventional approaches nonlinear fibers and enabled by low-loss (<2 dB) input coupling high nonlinearity silicon nitride, which can provide two octaves spectral broadening with energies only 110 pJ. Following self-referencing accomplished mixing 780-nm...
Abstract Optical frequency combs have revolutionized optical metrology and are being actively investigated in a number of applications outside pure metrology. For reasons cost, robustness, performance, flexibility, the erbium fiber laser comb has emerged as most commonly used system many different designs been demonstrated. We review approaches taken design combs, including major building blocks underlying mode-locked laser, amplifier, supercontinuum generation actuators for stabilization comb.
Evolutionary algorithms (EAs) are heuristic randomized which, by many impressive experiments, have been proven to behave quite well for optimization problems of various kinds. In this paper a rigorous theoretical complexity analysis the (1 + 1) evolutionary algorithm separable functions with Boolean inputs is given. Different mutation rates compared, and use crossover operator investigated. The main contribution not result that expected run time Θ(n ln n) n variables but methods which can be...
It is often claimed that Evolutionary Algorithms are superior to other optimization techniques, in particular, situations where not much known about the objective function be optimized. In contrast Wolpert and Macready (1997) proved all techniques have same behavior — on aver age over f : X → Y finite sets. This result called No Free Lunch Theorem. Here different scenarios of presented. argued why scenario which Theorem based does model real life optimization. For more realistic it differ...
Although evolutionary algorithms (EAs) are often successfully used for dynamically changing problems, there only few theoretical results about EAs dynamic objective functions. Here, the runtime of (1+1) EA is theoretically analyzed a variant ONEMAX. The main focus lies on determining degree change fitness function, where expected rises from polynomial to super-polynomial. proofs presented show methods how rigorously analyze
Evolutionary algorithms (EAs) are heuristic randomized which, by many impressive experiments, have been proven to behave quite well for optimization problems of various kinds. In this paper, a rigorous complexity analysis the (1+1) evolutionary algorithm linear functions with Boolean inputs is given. The carried out different mutation rates. main contribution paper not result that expected run time at most /spl Theta/(n ln n) n variables, but presentation methods showing how can be rigorously.
Passively mode-locked lasers with semiconductor saturable absorption mirrors are attractive comb sources due to their simplicity, excellent self-starting properties, and environmental robustness. These lasers, however, can have an increased noise level wake mode instabilities. Here, we investigate the dynamics in detail using a combination of evolutionary dynamical methods. We describe pulse generation from when stable exists evolution instability no exists. then calculate spectrum pulse,...
Precise determinations of transition frequencies simple atomic systems are required for a number fundamental applications such as tests quantum electrodynamics (QED), the determination constants and nuclear charge radii. The sharpest in hydrogen occurs between metastable 2S state 1S ground state. Its frequency has now been measured with almost 15 digits accuracy using an optical comb cesium clock reference [1]. A recent measurement – 2P3/2 muonic is significant contradiction to data if QED...
Estimation of distribution algorithms (EDAs) try to solve an optimization problem by finding a probability focussed around its optima. For this purpose they conduct sampling-evaluation-adjustment cycle, where search points are sampled with respect distribution, which is adjusted according the evaluation points. Although there many successful experiments suggesting usefulness EDAs, only few rigorous theoretical results apart from convergence without time bounds. Here we present first runtime...
We demonstrate optical frequency transfer over an 1840 km underground fiber link using a single-span stabilization. To compensate for more than 420 dB of attenuation the light we use twenty Erbium doped amplifiers along entire and two additional Brillouin amplifiers. The good passive stability our allows us to reach short term instabilities expressed as modified Allan deviation 3 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-15</sup>...
Evolutionary algorithms (EAs) are randomized search strategies that have turned out to be efficient for somewhat different optimization problems. In order understand the behavior of EAs, one is also interested in examples where EAs need exponential time find an optimal solution. Until now only artificial this kind were known. An example with a clear and simple structure presented. It can described by short formula, it polynomial degree 3, instance well-known problem, theoretically...
We describe the successful coupling of CEC and capillary HPLC with recently developed atmospheric-pressure laser ionization (APLI) method. APLI is suitable for selectively sensitively ionizing nonpolar aromatic compounds at ambient pressure subsequent mass-selective detection. The polycyclic hydrocarbons used as analytes are first separated either by on a silica-based monolithic column or HPLC. eluent, along sheath flow, volatilized microelectrospray then ionized excimer (KrF*) radiation via...