Functional integration through femtosecond laser-induced nano-structuration of glass

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Non-ablative femtosecond laser processing of transparent substrates involves cumulative, multi-timescale dynamics that hinder precise control of induced structural modifications. Here, we demonstrate a feedback-compatible diagnostic based on mid-infrared transmission monitoring using a continuous-wave QCL emitting at 4.46 µm. This approach enables in situ observation of structural dynamics induced by femtosecond laser irradiation at repetition rates up to 250 kHz. The technique shows sensitivity to key tran

Fast ions have been observed to be accelerated in the presence of Edge Localised Modes (ELMs) and MHD activity on the Tokamak & aacute; Configuration Variable. The acceleration time, velocity-space and frequency dynamics have been resolved by analysing the fast-ion losses measured using a unique Fast Ion Loss Detector (FILD) that allows microsecond velocity-space mapping. The findings presented herein complement and extend previous studies done at the Asdex Upgrade Tokamak and show a decorrelation between t

Wavelength‐tunable pulsed lasers have garnered significant research interest due to their critical role in applications requiring precise spectral matching, such as wavelength‐division multiplexing and spectroscopic analysis. Although recent hybrid architectures integrating saturable absorbers with wavelength‐selective components have enabled notable progress, these systems remain constrained by two fundamental challenges: excessive coupling losses and complex alignment procedures. Here, a compact wavelengt

TCV experiments and novel theoretical studies have addressed key questions regarding the operational space of negative triangularity (NT) plasmas in view of an L-mode NT reactor, in terms of stability, performance properties and core-edge integration. We show that reducing the top triangularity (δtop) to more negative values induces an H-L back transition, confirming the direct dependence between H-mode existence and access to 2nd ballooning stability region. We also show that the X-point δ can prohibit H-m

The rapidly evolving field of 2D materials has developed a plethora of emerging micro/nano devices where atomically-thin materials play a fundamental role. In most cases, this implies the need of nanostructuring them, but due to their delicate nature, conventional lithographies using electrons or ions can deteriorate their performance. Thermal scanning probe lithography (t-SPL) is an advanced direct-write method that uses a heated nanotip for 2D and 3D subtractive/additive manufacturing [1]. The creation of

Linear crystal defects called dislocations are one of the most fascinating concepts in materials science that govern mechanical and optoelectronic properties of many materials across a broad range of application. Three-dimensional (3-D) study of dislocation network is in principle accessible by conventional tomographic and stereoscopic techniques in Transmission Electron Microscopy (TEM). In these techniques in general the need to tilt the specimen for acquiring image series over large tilt ranges remain ho

Fast query and transaction processing is the goal of 40 years of database research and the reason of existence for many new database system architectures. In data management, system performance means acceptable response time and throughput on critical-path operations, ideally with scalability guarantees. Performance is improved with top-of-the line research on data processing algorithms; efficiency, however, is contingent on seamless collaboration between the database software and hardware and storage devic

Purpose – Since pulsed lasers are mainly used in selective laser sintering (SLS) – contrarily to selective laser melting (SLM) – only the exterior of the powder particles is molten while their core stays solid. The purpose of this paper is to investigate the binding mechanism between two particles of titanium powder. Design/methodology/approach – A dedicated experimental setup is used to isolate the particles. They are then irradiated by the laser. SEM micrographs are taken at each step and image analysis i

In support of the TCV experimental campaign aiming at studying H-mode plasmas with snowﬂake (SF) divertor, free boundary equilibrium and stability studies were performed with the SPIDER and KINX codes. Due to the high ﬂexibility of plasma shaping capabilities of TCV, SF divertor conditions can be reached for various plasma geometries. However, at high plasma current some conﬁgurations require poloidal ﬁeld (PF) coil currents close to the machine limit. This is particularly import

Nanoparticles are interesting for biomedical imaging as novel non- fluorescent non-bleaching labels. We present the characterization of freely diffusing nanoparticles using third harmonic generation correlation spectroscopy by illumination with a focussed pulsed femtosecond laser. We present the optical system as well as first spectroscopic results on nanoparticles.

We present a novel Fourier domain method for microscopic imaging - so- called k-microscopy - with lateral resolution independent of the detection numerical aperture. The concept is based on sample illumination by a lateral fringe- pattern of varying spatial frequency, which probes the lateral spatial frequency or k- spectrum of the sample structure. The illumination pattern is realized by interference of two collimated coherent beams. Wavelength tuning is employed for modulation of the fringe spacing. The u

With the use of a Bessel-like illumination beam produced by an axicon lens an extended depth of field can be achieved. The resulting illumination pattern exhibits a strong central lobe extending over 300um along the optical axis without diffraction. Here we present a fast digital focusing algorithm to correct for remaining out of focus artifacts, manifest in sidelobes for out of focus scatterers, due to the decoupled Gaussian detection. The waist of the detection in the focal plane is 2.1um, with a Rayleigh

Biomimetic apatite coatings were obtained by soaking chemically treated titanium in SBF with different HCO3- concentration. XRD, FTIR and Raman analyses were used to characterize phase composition and degree of carbonate substitution. The microstructure, elemental composition and preferred alignment of biomimetically precipitated crystallites were characterized by cross-sectional TEM analyses. According to XRD, the phase composition of precipitated coatings on chemically pre-treated titanium after exposure

A 3D imager is presented capable of computing the depth map as well as the intensity scale of a given scene. The heart of the system is a two-dimensional array of single photon avalanche diodes fabricated in standard CMOS technology. The diodes exhibit low noise equivalent power, high dynamic range and superior linearity. The 3D imager achieves sub-millimetric precision at depth-of-field of a few meters. It operates using a standard LASER source pulsed at 50MHz with 40mW peak power and requires no mechanica

The extreme shaping capabilities of the TCV tokamak have been used to investigate the effect of plasma geometry on the confinement of non-recycling trace impurities injected by means of the laser blow-off technique. The progression of the injected silicon in the core of TCV Ohmic limiter plasmas was followed by the 200-channel soft x-ray (SXR) photodiode array with good spatial and temporal resolution. The results show that the plasma triangularity and elongation play an important role in the impurity confi

First results and analysis of second harmonic generation with a Nd:YAG laser working in the long pulse, free running mode are presented in this paper. Second harmonic generation conversion efficiencies of up to 17.5% and pulse powers of 162W have been generated with a free running Nd:YAG laser and a KTP non-linear crystal. The conversion efficiency is limited by a saturation effect and optical damage occurring at similar to50 times lower peak intensities than in the Q-switch mode. The saturation and damage

Research on the Alcator C-Mod tokamak [1] is focused on high particle- and power-density plasma regimes to understand particle and energy transport in the core, the dynamics of the H-mode pedestal, and scrape-off layer and divertor physics. The auxiliary heating is provided exclusively by RF waves, and both the physics and technology of RF heating and current drive are studied. The momentum which is manifested in strong toroidal rotation, in the absence of direct momentum input, has been shown to be transpo

The Aspect Integrator Platform (AIP) from ABB was designed to build the next generation of industrial automation applications. This platform is part of a set of products that provide the means to model, control and supervise continuous or discrete processes in various market domains, ranging from chemical and metal to paper and consumer industries. Each product works at a different level in the manufacture process, having distinct safety and real time requirements, but all of them rely on a common architect

Neoclassical transport and a particle confinement are analysed for three 3-D reactor designs-the QAS3, the ST/sphellamak hybrid and the sphellamak-using the VENUS code. It is observed that neither the QAS3 nor the ST/sphellamak is truly aquasi-axisymmetric configuration. Thus the transport is governed by the helical deformation of the magnetic Field strength, and these configurations do not effectively confine the trapped a particles. On the other hand, the sphellamak is a nearly isodynamic structure in the

We propose in this paper a novel method for generating the pump and probe signals for a Brillouin fibre sensor. It is based on the injection locking of two distinct semiconductor lasers, that makes possible the generation of high purity beat signals in the microwave frequency range. Such a technique can be used either in the pulsed pump-probe technique or the new correlation-based technique. Furthermore novel devices, such as laser modules presenting integrated electro-absorption modulators, can be exploite

Functional integration through femtosecond laser-induced nano-structuration of glass

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Laser-based in situ monitoring of femtosecond-laser in-bulk processing of glass

Dynamics of the Fast-ion Acceleration in Type-i Elmy H-mode Scenarios on the Tcv Tokamak

Wavelength Tunable Pulsed Lasers Enabled by a Versatile Metafiber Functioning as Both Saturable Absorber and Filter

NEGATIVE TRIANGULARITY TOKAMAK OPERATION IN TCV

Thermomechanical nanocutting of 2D materials using thermal scanning probe lithography

Three-dimensional electron imaging of dislocations from a single sample tilt

Databases and Hardware: The Beginning and Sequel of a Beautiful Friendship

Study of the inter-particle necks in selective laser sintering

Optimization of the snowflake diverted equilibria in the TCV tokamak

Characterization of Nanoparticles Using Non-linear Correlation Spectroscopy

k-Microscopy: resolution beyond the diffraction limit

Enhancement of extended depth of field by digital focusing

Biomimetic apatite coatings - Carbonate substitution and preferred growth orientation

Toward a 3-D Camera Based on Single Photon Avalanche Diodes

Effects of plasma shape on laser blow-off injected impurity transport in TCV

Second harmonic generation with free running Nd : YAG laser

Overview of recent Alcator C-Mod research

A Software Architecture for Industrial Automation

Neoclassical transport and alpha particle confinement in novel 3-D reactor systems

2-laser injection-locking configuration for Brillouin fibre sensors