Frequency combs have made optical metrology accessible to hundreds of laboratories worldwide and they have set new benchmarks in multi-species trace gas sensing for environmental, industrial and ...medical applications. However, current comb spectrometers privilege either frequency precision and sensitivity through interposition of a cw probe laser with limited tuning range, or spectral coverage and measurement time using the comb itself as an ultra-broadband probe. We overcome this restriction by introducing a comb-locked frequency-swept optical synthesizer that allows a continuous-wave laser to be swept in seconds over spectral ranges of several terahertz while remaining phase locked to an underlying frequency comb. This offers a unique degree of versatility, as the synthesizer can be either repeatedly scanned over a single absorption line to achieve ultimate precision and sensitivity, or swept in seconds over an entire rovibrational band to capture multiple species. The spectrometer enables us to determine line center frequencies with an absolute uncertainty of 30 kHz and at the same time to collect absorption spectra over more than 3 THz with state-of-the-art sensitivity of a few 10
cm
. Beyond precision broadband spectroscopy, the proposed synthesizer is an extremely promising tool to force a breakthrough in terahertz metrology and coherent laser ranging.
We report on the realization of a continuous-wave light source based on nonlinear interaction in KBBF at a wavelength of 191 nm. More than 1.3 mW of deep-ultraviolet power was generated in a ...mechanically robust setup pumped by an amplified grating stabilized diode laser. Mode hop-free tuning over 40 GHz at 191 nm could be demonstrated.
Sodium Guide Star (R)Evolution Enderlein, Martin; Kaenders, Wilhelm G.
Optik & Photonik,
December 2016, 20161201, Letnik:
11, Številka:
5
Journal Article
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After several decades of dedicated laser development for astronomical adaptive optics, this is the first time that high output power is combined with an optimized laser format, maximizing the ...coupling of the laser light to the sodium atoms in the Earth's atmosphere. By re‐emission of the absorbed light, an artificial star is created that is used to measure atmospheric distortions and correct astronomical images faster and more reliably than ever before. The effort of the collaboration between the European Southern Observatory (ESO), Toptica Photonics, and MPB Communications has been recognized recently with the third prize of the Berthold Leibinger Innovation Award.
Live microscopy techniques (i.e., differential interference contrast, confocal microscopy, etc.) have enabled the understanding of the mechanisms involved in cells and tissue formation. In long-term ...studies, special care must be taken in order to avoid sample damage, restricting the applicability of the different microscopy techniques. We demonstrate the potential of using third-harmonic generation (THG) microscopy for morphogenesis/embryogenesis studies in living Caenorhabditis elegans (C. elegans). Moreover, we show that the THG signal is obtained in all the embryo development stages, showing different tissue/structure information. For this research, we employ a 1550-nm femtosecond fiber laser and demonstrate that the expected water absorption at this wavelength does not severely compromise sample viability. Additionally, this has the important advantage that the THG signal is emitted at visible wavelengths (516 nm). Therefore, standard collection optics and detectors operating near maximum efficiency enable an optimal signal reconstruction. All this, to the best of our knowledge, demonstrates for the first time the noninvasiveness and strong potential of this particular wavelength to be used for high-resolution four-dimensional imaging of embryogenesis using unstained C. elegans in vivo samples.
We present a simple method for narrowing the intrinsic Lorentzian linewidth of a commercial ultraviolet grating extended-cavity diode laser (TOPTICA DL Pro) using weak optical feedback from a long ...external cavity. We achieve a suppression in frequency noise spectral density of 20 dB measured at frequencies around 1 MHz, corresponding to the narrowing of the intrinsic Lorentzian linewidth from 200 kHz to 2 kHz. Provided additional active low-frequency noise suppression and long-term drift compensation, the system is suitable for experiments requiring a tunable ultraviolet laser with narrow linewidth and low high-frequency noise, such as precision spectroscopy, optical clocks, and quantum information science experiments.
Ultra-precise optical clocks in space will allow new studies in fundamental physics and astronomy. Within an European Space Agency (ESA) program, the “Space Optical Clocks” (SOC) project aims to ...install and to operate an optical lattice clock on the International Space Station (ISS) towards the end of this decade. It would be a natural follow-on to the ACES mission, improving its performance by at least one order of magnitude. The payload is planned to include an optical lattice clock, as well as a frequency comb, a microwave link, and an optical link for comparisons of the ISS clock with ground clocks located in several countries and continents. Within the EU-FP7-SPACE-2010-1 project No. 263500, during the years 2011–2015 a compact, a modular and robust strontium lattice optical clock demonstrator has been developed. The goal performance is a fractional frequency instability below 1×10−15τ−1/2 and a fractional inaccuracy below 5 ×10−17. Here we describe the current status of the apparatus' development, including the laser subsystems. The robust preparation of cold 88Sr atoms in a second-stage magneto-optical trap (MOT) is achieved.
Des horloges optiques ultra-précises envoyées dans l'espace permettront de nouvelles avancées dans les domaines de la physique fondamentale et de l'astronomie. Le projet « Horloges optiques spatiales » (SOC pour Space Optical Clocks), qui fait partie d'un programme de l'Agence spatiale européenne (ESA), a pour but d'envoyer et de faire fonctionner une horloge à réseau optique à bord de la station spatiale internationale (ISS) vers la fin de la décennie. Cette mission serait un successeur de la mission ACES, avec une performance au moins dix fois meilleure. Il est prévu que la charge utile inclue une horloge à réseau optique ainsi qu'un peigne de fréquences, un lien micro-onde et un lien optique pour comparer cette horloge avec d'autres situées sur Terre, dans plusieurs pays et continents. Entre 2011 et 2015, un démonstrateur d'horloge à réseau optique utilisant des atomes de strontium, compact, modulaire et robuste a été développé dans le cadre du projet n∘ 263500 EU-FP7-SPACE-2010-1. La performance visée est une stabilité de fréquence fractionelle meilleure que 1×10−15τ1/2 et un exactitude fractionelle meilleure que 5×10−17. Dans cette article, nous décrivons l'état d'avancement du développement du dispositif, incluant les sous-systémes laser. La préparation d'atomes froids de 88Sr dans un piége magnéto-optique sur raie étroite est démontrée.
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