Browsing by Subject "Laser beams"
Now showing items 1-20 of 20
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Alignment of terahertz transmission setups with free-space laser photoconductive switches
(Institute of Electrical and Electronics Engineers (IEEE), 2022)
Conference lecture
Restricted access - publisher's policyA systematic procedure for ensuring perfect alignment of Photoconductive Antennas (PCA) in transmittance measure setups with free-space laser PCA gap feeding and mechanical adjust of silicon substrate lenses is presented. ... -
Analysis of beam wander effects for a horizontal-path propagating Gaussian-beam wave: focused beam case
(SPIE-INT SOCIETY OPTICAL ENGINEERING, 2007-08-31)
Article
Open AccessFailure of the first-order Rytov approximation to properly predict the scintillation index of a large-aperture focused beam, or an uplink collimated (or focused) beam, has been discussed in several recent publications, ... -
Confocal flowmeter based on self-mixing interferometry for real-time velocity profiling of turbid liquids flowing in microcapillaries
(2019-08-19)
Article
Open AccessWe propose a new confocal device for flow profiling in microcapillaries. A viewfinder system is developed using a visible light microscope, allowing focusing with high precision an 830 nm Fabry-Perot laser diode on a ... -
Cost-effective microfabrication of sub-micron-depth channels by femto-laser anti-stiction texturing
(2020-02-26)
Article
Open AccessMicro Electro Mechanical Systems (MEMS) and microfluidic devices have found numerous applications in the industrial sector. However, they require a fast, cost-effective and reliable manufacturing process in order to compete ... -
Demonstration of a highly-sensitive tunable beam displacer with no use of beam deflection based on the concept of weak value amplification
(OSA, 2015-04-20)
Article
Open AccessWe report the implementation of a highly sensitive tunable beam displacer based on the concept of weak value amplification, that allows to displace the centroid of a Gaussian beam a distance much smaller than its beam width ... -
Flat focusing mirrors
(Institute of Electrical and Electronics Engineers (IEEE), 2015)
Conference report
Restricted access - publisher's policyWe present the flat focusing mirror - the dielectric mirrors capable to focus and image the narrow beams in reflections. The mirrors are flat, and transversally invariant, i.e. have no optical axis. We consider two different ... -
Influence of laser beam power and scanning speed on the macrostructural characteristics of AISI 316L and AISI 431 stainless steel depositions produced by laser cladding process
(2021-04-05)
Article
Open AccessIn the laser cladding process, control of the process parameters and knowledge of the characteristics of the materials used are essential for obtaining depositions with excellent metallurgical union, satisfactory dilution ... -
Laser wire emittance measurement line at CLIC
(2012)
Conference lecture
Open AccessA precise measurement of the transverse beam size and beam emittances upstream of the final focus is essential for ensuring the full luminosity at future linear colliders. A scheme for the emittance measurements at the ... -
Light dynamics in glass-vanadium dioxide nanocomposite waveguides with thermal nonlinearity
(2009-04)
Article
Open AccessWe address the propagation of laser beams in SiO2–VO2 nanocomposite waveguides with thermo-optical nonlinearity. We show that the large modifications of the absorption coefficient as well as notable changes of the ... -
Optical drills by dynamic high-order bessel beam mixing
(American Physical Society (APS), 2022-03-25)
Article
Open AccessOne of the key trends in laser material processing is the usage of structured laser beams. Collimated and focused Gaussian beams are the most common tools; however, more exotic beams can be beneficial too. For instance, ... -
Optical path length measurement of spherical dielectric shells with axicon-generated Bessel beams; applications to corneal sensing
(2021)
Conference lecture
Open AccessA custom aspheric axicon lens for corneal water content sensing, operating from 220 to 330 GHz, was evaluated with spherical, dielectric shell targets. The lens consisted of a hyperbolic back surface and conical front ... -
Preparation of engineered two-photon entangled states for multidimensional quantum information
(2003-05)
Article
Restricted access - publisher's policyWe put forward an experimentally feasible technique to generate engineered entangled states in d-dimensional Hilbert spaces in parametric down-conversion of photons. The scheme is based on the orbital angular momentum of ... -
Random number generation by coherent detection of quantum phase noise
(2020-02-17)
Article
Open AccessIn 2010 Qi et al. [Opt. Lett. 35(3), 312 (2010)] demonstrated a random number generator based on the drift of the phase of a laser due to spontaneous emission, The out-of-the-lab implementation of this scheme presents two ... -
Rotating acoustic drills by the interference of detuned vortices
(Institute of Electrical and Electronics Engineers (IEEE), 2022)
Conference report
Restricted access - publisher's policyWe present acoustic drill beams, structured sound beams exhibiting a dynamic intensity distribution that matches the shape of a helix. The intensity distribution rotates along the beam axis with controlled direction and ... -
Schädigungsparameter für Laserstrahlschweißverbindungen unter zyklischen, mehraxialen Belastungen
(Universitat Politècnica de Catalunya / Technische Universität Darmstadt, 2011)
Master thesis (pre-Bologna period)
Restricted access - author's decisionIn der Automobil- und Luftfahrtbranche werden Laserstrahlschweißverbindungen häufig benutzt. Die Technologie erlaubt eine effektive Verbindung dünnwandiger Leichtbaukonstruktionen. Bei schneller Fertigung ermöglicht sie ... -
Study of femtosecond laser beam focusing in a direct-write system
(Universitat Politècnica de Catalunya, 2016-07-22)
Master thesis
Open AccessDirect-write techniques appear as a versatile option in rapid-prototyping applications because they can directly transfer a custom pattern from a digital file. Lasers are a distinguished tool which allow to perform non-contact ... -
Study of heat sources interacting in integrated circuits by laser mirage effect
(2014-08-25)
Article
Restricted access - publisher's policyThis work exploits the mirage effect to analyze multiple heat sources thermally interacting in an integrated circuit (IC) by means of a probe IR laser beam, which strikes on the die lateral walls and passes through the die ... -
Super-collimation by axisymmetric diffractive metamirror
(2021-08-05)
Article
Restricted access - publisher's policyWe propose and demonstrate experimentally super-collimation of light beams by an axisymmetric diffractive metamirror—an axisymmetric concentric dielectric ring structure positioned in front of a mirror at a distance of ... -
Temporal analysis of laser beam propagation in the atmosphere using computer-generated long phase screens
(2008-02-04)
Article
Open AccessTemporal analysis of the irradiance at the detector plane is intended as the first step in the study of the mean fade time in a free optical communication system. In the present work this analysis has been performed for a ... -
VUV Frequency Comb by Cavity-Enhanced High Harmonic Generation on Solid Surfaces
(Optical Society of American (OSA), 2019)
Conference report
Restricted access - publisher's policyUsing an enhancement cavity, a sub-Watt power Ti:sapphire femtosecond frequency comb is enhanced to 24 W and 3rd, 5th and 7th harmonics are generated in a non-perturbative manner on the surface of thin AlN layer.
