319 research outputs found
Design, production and characterization of mirrors for ultra-broadband, high-finesse enhancement cavities
To enable the enhancement of few-cycle pulses in high-finesse passive optical
resonators, a novel complementary-phase approach is considered for the
resonator mirrors. The design challenges and first experimental results are
presented.Comment: 3 page
Directly diode-pumped, Kerr-lens mode-locked, few-cycle Cr:ZnSe oscillator
Lasers based on Cr-doped II-VI material, often known as the
Ti:Sapphire of the mid-infrared, can directly provide few-cycle pulses with
super-octave-spanning spectra, and serve as efficient drivers for generating
broadband mid-infrared radiation. It is expected that the wider adoption of
this technology benefits from more compact and cost-effective embodiments.
Here, we report the first directly diode-pumped, Kerr-lens mode-locked
Cr-doped II-VI oscillator pumped by a single InP diode, providing
average powers of over 500 mW and pulse durations of 45 fs - shorter than six
optical cycles at 2.4 m. These correspond to a sixty-fold increase in peak
power compared to the previous diode-pumped record, and are at similar levels
with respect to more mature fiber-pumped oscillators. The diode-pumped
femtosecond oscillator presented here constitutes a key step towards a more
accessible alternative to synchrotron-like infrared radiation, and is expected
to accelerate research in laser spectroscopy and ultrafast infrared optics.Comment: 8 pages, 5 figure
Starting designs for broadband chirped mirrors
The chirped mirror (CM) is one of the key elements in ultrafast optics. We
investigate a problem of a CM designing. The series of starting designs for broadband
CM are reported. The appropriate starting design can significantly simplify a problem of
design searching, and improved a performance of a final solution. The acceptable
performance of CM was achieved by optimization one of the proposed starting design.
The achieved design has comparable performance in comparison with the best design
which was realized up to now
Features of the super prism effect in multilayer dielectric coatings
We demonstrate that the strong change of reflected beam intensity in the
spectral range of the super-prism effect not allow to use periodic multilayer coatings as
effective wavelength division multiplexing devices. But using chirped mirrors that are
one of the key elements in ultrafast optics can solve this problem with success
Measurement setup for the determination of the nonlinear refractive index of thin films with high nonlinearity
The exploitation of nonlinear effects in multi-layer thin films allows for optics with novel functions, such as all-optical switching and frequency conversion. In this contribution, an improved interferometric setup for the measurement of the nonlinear refractive index in dielectric substrates and deposited single layers is presented. The setup is based on the wave front deformation caused by the self-focusing in the measured samples. Additionally, measurement results for a highly nonlinear material, indium-Tin-oxide (ITO) are presented with respect to the materials power handling capabilities and compared to values from other materials. © COPYRIGHT SPI
Synthesis, fabrication and characterization of a highly-dispersive mirrors for the 2 µm spectral range
High photon flux table-top coherent extreme ultraviolet source
High harmonic generation (HHG) enables extreme ultraviolet radiation with
table-top setups. Its exceptional properties, such as coherence and
(sub)-femtosecond pulse durations, have led to a diversity of applications.
Some of these require a high photon flux and megahertz repetition rates, e.g.
to avoid space charge effects in photoelectron spectroscopy. To date this has
only been achieved with enhancement cavities. Here, we establish a novel route
towards powerful HHG sources. By achieving phase-matched HHG of a megahertz
fibre laser we generate a broad plateau (25 eV - 40 eV) of strong harmonics,
each containing more than photons/s, which constitutes an increase by
more than one order of magnitude in that wavelength range. The strongest
harmonic (H25, 30 eV) has an average power of 143 W (
photons/s). This concept will greatly advance and facilitate applications in
photoelectron or coincidence spectroscopy, coherent diffractive imaging or
(multidimensional) surface science
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