Optica’s Post

I am happy to inform that our work was presented in the SPIE (The International Society of Optics and Photonics) conference proceedings, and the paper got published on 9th May,2024. This paper explains the interaction of lamb waves with sensors in carbon fiber layered composite with Symmetric and Asymmetric configurations. The link of the paper is given below. https://lnkd.in/eHZh_gce #Structural Health monitoring in Composite Material #NDE

Luying Yi, Xiaogang Liu and colleagues introduce an imaging technique named “stochastic photoluminescence and compressed encoding,” or SPACE. SPACE leverages randomly arrayed lanthanide transducers as photonic encoders to capture various excitation wavelengths in a single image, recorded by a charge-coupled device. This approach enables the reconstruction of multiple scenes from this encoded image across four wavelength channels: X-rays (0.089 nm), ultraviolet (375 nm), and two near-infrared bands (808 and 1,532 nm), with the ability to expand to more channels through multi-layer encoders. SPACE enables multi-channel imaging for depth visualization and multi-spectral X-ray analysis, offering broad multi-spectral sensitivity and on-chip compatibility. This makes it a versatile tool for applications in materials characterization, bioimaging, remote sensing, and astronomy. Online now in #Matter https://lnkd.in/eiZwsSRb

Quantum Entanglement visualised for the first time using Holographic Techniques The Ying and The Yang Below the visualisation of the Wavefunction of two entangled Photons. Reference: Zia. D., Dehghan. N., D’Errico. A., et al, Interferometric imaging of amplitude and phase of spatial biphoton states, Nature Photonics, (2023), DOI: 10.1038/s41566–023–01272–3 Feature image credit: Biphoton state holographic reconstruction. Nature Photonics (2023). DOI: 10.1038/s41566-023-01272-3

We're delighted to share that the article "Investigating Isogyres in Ferrofluids and Horocycles from Parlaseric Circle in a Ferrocell" by Dr. Alberto Tufaile and Dr. Adriana Pedrosa Biscaia Tufaile from University of São Paulo has been published online in Journal of Optics and Photonics Research.   Abstract: This study explored the complex relationship between magnetic fields and light polarization in thin films of ferrofluid. Utilizing techniques such as polarized light imaging, multipolar expansion, and Mueller matrix formalism, this work investigated the formation of isogyres, which are distinct patterns observed when polarized light passes through the ferrofluid under various magnetic field configurations. The analysis revealed that the alignment of nanoparticles in response to the magnetic field resulted in the formation of a diffraction grating, influencing light polarization. Through the application of Stokes vectors and Mueller matrices, we gained insights into the complex interplay between magnetic fields and optical properties. The experiment presents the evolution of isogyres from straight lines to parabolas under the influence of a hexapolar magnetic field. The Mueller matrix effectively represented the magnetic field's impact on polarized light, highlighting dark regions corresponding to isogyres. We also report the formation of some patterns related to atmospheric optics and their analogy with the formation of patterns of the parlaseric circle and the luminous horocycle. Feel free to click on the link to read and share the article:  https://lnkd.in/gAx69K7i #isogyres #luminoushorocycles #parlasericcircle #ferrocell #ferrofluid

Check on our recent publication: “Terahertz spectroscopy and imaging up to 20 THz based on organic crystals,” published as part of the proceedings of the last Photonics West 2024 conference. The DOI of our paper is https://lnkd.in/dwMNGX5a.

🔎 A beautiful 3D visualization of a sillimanite-garnet migmatitic gneiss - useful for the quantitative 3D analysis of garnet deformation during migmatization. The samples come from the Permian lower continental crust of the Valpelline Series in the Western Alps. 📸 Imaging was performed via the EXCITE network by Dr. Yuntao Ji (Utrecht University) for EXCITE transnational access user Fabiola Caso (University of Milan - Università degli Studi di Milano) 🔬 ZEISS Microscopy Xradia 610 Versa 3D X-ray Microscope (#XCT) 📍 Earth Simulation & HPT Laboratory, Utrecht University #Horizon2020 #EU_H2020 #EXCITE_network #EXCITE #microscopy #electronmicroscopy #xraymicroscopy #xraytomography #microCT #openaccess #geoscience #earthscience

Published in Applied Optics [#OPG_AO], a Université Grenoble Alpes research team demonstrated an accurate high-sensitivity method for cavity spectroscopy: https://ow.ly/Z8ec50R53wI The technique combines the optical feedback locking of a laser diode to a cavity mode with heterodyne detection at cavity transmission after imposing frequency sidebands to the laser. As a result, the team could detect side band power down to fW levels even with a small carrier power transmitted through the cavity. Written by: Marianne Beaumont, Irène Ventrillard, and Daniele Romanini #ScienceAndTechnology #Spectroscopy #Optics #LaserScience

Circular polarization revisited. While circular polarization is a familiar concept, it can be confusing in reality, in particular for simulation in time domain. FDTD simulation can easily give the frequency-domain results in space. However the definitions in time domain are frequently used. This leads to questions of left-/right-handed, clockwise/counterclockwise circular polarization, observer's location etc. I presented a short paper at 2024 Photonics West: , “Unique handedness of a circularly-polarized plane wave in simulation,”  https://lnkd.in/ghEBGCFb. I summarized the discrepancy from classical books, pointed out the opposite handedness in time and space, introduced the propagation direction k in the definition, and proposed a new triad of E1, E2 and propagation direction k to determine the handedness in time domain, which will be unique. Hopefully this concept can be clear in simulation, and professors can adopt it in textbooks and in classrooms. With the propagation direction involved, no observer is used and the handedness is objective.

Why 511 keV? 511 keV refers to the energy of the photons produced in the annihilation of an electron and a positron. This specific energy is significant because it is equal to the rest mass energy of an electron (or positron), which is given by the equation (E = mc^2). This energy is fundamental in physics, particularly in fields such as positron emission tomography (PET) in medical imaging and in the study of particle interactions. #PET #NUCLEARMMEDICINE

Dear all, My PhD at IRT b-com and IMT Atlantique deals with #holograms of high definition and enhanced quality. More precisely, with Antonin Gilles, Kevin Heggarty and Bruno Fracasso, we developed a method that reduces the computational load associated with the generation of these holograms. This technique relies on a view-specific layer-based stereogram approach combined with a view-dependent error diffusion algorithm. It selects the light waves of a 3D scene that reach a specific viewing area and leverages this particular configuration to apply an error diffusion algorithm. Two papers explain in details our method and are available here: https://lnkd.in/eKu8yUcg & https://lnkd.in/eS9NTn8e. #holography