Publications associées à Divergence de faisceau

Photothermal spectroscopy on-chip sensor for the measurement of a PMMA film using a silicon nitride micro-ring resonator and an external cavity quantum cascade laser

Laser-based mid-infrared (mid-IR) photothermal spectroscopy (PTS) represents a selective, fast, and sensitive analytical technique. Recent developments in laser design permits the coverage of wider spectral regions in combination with higher power, enablin ...

Walter De Gruyter Gmbh2024

Mode-Specific Coupling of Nanoparticle-on-Mirror Cavities with Cylindrical Vector Beams

Christophe Marcel Georges Galland, Valeria Vento, Sachin Suresh Verlekar, Philippe Andreas Rölli

Nanocavities formed by ultrathin metallic gaps permitthe reproducibleengineering and enhancement of light-matter interaction, withmode volumes reaching the smallest values allowed by quantum mechanics.While the enhanced vacuum field in metallic nanogaps ha ...

2023

Transfer learning application of self-supervised learning in ARPES

Gabriel Aeppli

There is a growing recognition that electronic band structure is a local property of materials and devices, and there is steep growth in capabilities to collect the relevant data. New photon sources, from small-laboratory-based lasers to free electron lase ...

IOP Publishing Ltd2023

Experimental demonstration of dynamic spatiotemporal structured beams that simultaneously exhibit two orbital angular momenta by combining multiple frequency lines, each carrying multiple Laguerre-Gaussian modes

Tobias Kippenberg, Maxim Karpov, Zhe Zhao, Hao Song, Xinzhou Su

In general, there are different, relatively independent forms of orbital angular momenta at a given propagation distance, which might exhibit different dynamic spatial characteristics. One type involves a beam with a helical phase-front that rotates around ...

Optica Publishing Group2022

Generation of OAM-carrying space-time wave packets with time-dependent beam radii using a coherent combination of multiple LG modes on multiple frequencies

Tobias Kippenberg, Maxim Karpov, Zhe Zhao, Hao Song, Xinzhou Su

Space-time (ST) wave packets, in which spatial and temporal characteristics are coupled, have gained attention due to their unique propagation characteristics, such as propagation invariance and tunable group velocity in addition to their potential ability ...

Optica Publishing Group2022

Study of Negative Ion Beamlets Produced in SPIDER by Beam Emission Spectroscopy

Riccardo Agnello

Among the beam diagnostics routinely employed in source for production of ion of deuterium (SPIDER), beam emission spectroscopy (BES) provides valuable information for beam characterization, thus driving source optimization methods. In particular, this tec ...

2022

Structured light engineering using a photonic nanojet

Toralf Scharf, Maryam Yousefi, Daniel Necesal

In this Letter, we present the photonic nanojet as a phenomenon in a structured light generator system that is implemented to modify the source focal spot size and emission angle. The optical system comprises a microlens array that is illuminated by a focu ...

OPTICAL SOC AMER2021

Laser treatment systems and methods for in-situ laser shock peening (lsp) treatment of parts during production thereof by a selective laser sintering or melting (sls/slm) process, and additive manufacturing systems and methods implementing the same

Roland Logé, Nikola Kalentics

There is described, in accordance with a first aspect of the invention, a laser treatment system and method for, in particular, imparting beneficial residual stresses into a desired part (P) during production thereof by a Selective Laser Sintering or Melti ...

2021

Rapid melting and revitrification as an approach to microsecond time-resolved cryo-electron microscopy

Marcel Drabbels, Ulrich Lorenz, Pavel Olshin, Jonathan Mark Voss, Oliver Florian Harder

Proteins typically undergo dynamics on the microsecond to millisecond timescale, which is much faster than the time resolution of cryo-electron microscopy. Here, we propose a novel approach for microsecond time-resolved cryo-electron microscopy that involv ...

Elsevier2021

Structured light generation by refractive-diffractive micro optical array illuminators

Maryam Yousefi

Structured light generation having broad applications in different optical fields, is the topic of this thesis. Our structured light generation strategy is based on applying periodic microoptical elements at the refraction-diffraction limit, under a focuse ...

EPFL2021