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Abstract Single Pulse All Optical Switching represents the ability to reverse the magnetization of a nanostructure using a femtosecond single laser pulse without any applied field. Since the first switching experiments carried out on GdFeCo ferrimagnets, this phenomena has been only recently extended to a few other materials, MnRuGa alloys and Tb/Co multilayers with a very specific range of thickness and composition. Here, we demonstrate that single pulse switching can be obtained for a large range of rare earth–transition metal multilayers, making this phenomenon much more general. Surprisingly, the threshold fluence for switching is observed to be independent of the laser pulse duration. Moreover, at high laser intensities, concentric ring domain structures are induced. These striking features contrast to those observed in Gd based materials pointing towards a different reversal mechanism. Concomitant with the demonstration of an in-plane magnetization reorientation, a precessional reversal mechanism explains all the observed features.

Este trabajo presenta la estructura tecnológica observada en los niveles B y Bb (Boreal) de La Cativera, donde se observa una dualidad entre explotaciones laminares simplificadas y una producción de lascas cortas normalizadas. Una nueva datación inédita refuerza la posición cronológica de estos niveles pese a que las estrategias de talla de los mismos difieren significativamente de las documentadas en yacimientos sincrónicos. Los niveles B y Bb coinciden en el tiempo con los conjuntos del Mesolítico de Muescas y Denticulados, sin embargo el análisis tecnológico de la industria lítica lo pone en relación más directa con los conjuntos del Magdaleniense final y/o Epipaleolítico microlaminar propios del Tardiglaciar.

Single Pulse All Optical Switching represents the ability to reverse the magnetization of a nanostructure using a femtosecond single laser pulse without any applied field. Since the first switching experiments carried out on GdFeCo ferrimagnets, this phenomena has been only recently extended to a few other materials, MnRuGa alloys and Tb/Co multilayers with a very specific range of thickness and composition. Here, we demonstrate that single pulse switching can be obtained for a large range of rare earth-transition metal multilayers, making this phenomenon much more general. Surprisingly, the threshold fluence for switching is observed to be independent of the laser pulse duration. Moreover, at high laser intensities, concentric ring domain structures are induced. These striking features contrast to those observed in Gd based materials pointing towards a different reversal mechanism. Concomitant with the demonstration of an in-plane magnetization reorientation, a precessional reversal mechanism explains all the observed features., (© 2023. Springer Nature Limited.)

The impact of plasmonic surface lattice resonances on the magneto-optical properties and energy absorption efficiency has been studied in arrays of [Co/Gd/Pt] N multilayer nanodisks. Varying the light wavelength, the disk diameter, and the period of the array, it is demonstrated that surface lattice resonances allow all-optical single pulse switching of [Co/Gd/Pt] N nanodisk arrays with an energy 400% smaller than the energy needed to switch a continuous [Co/Gd/Pt] N film. Moreover, the magneto-optical Faraday effect is enhanced at the resonance condition by up to 5,000%. The influence of the disk diameter and array period on the amplitude, width and position of the surface lattice resonances is in qualitative agreement with theoretical calculations and opens the way to designing magnetic metasurfaces for all-optical magnetization switching applications., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

When exciting a magnetic material with a femtosecond laser pulse, the amplitude of magnetization is no longer constant and can decrease within a time scale comparable to the duration of the optical excitation. This ultrafast demagnetization can even trigger an ultrafast, out of equilibrium, phase transition to a paramagnetic state. The reciprocal effect, namely an ultrafast remagnetization from the zero magnetization state, is a necessary ingredient to achieve a complete ultrafast reversal. However, the speed of remagnetization is limited by the universal critical slowing down which appears close to a phase transition. Here we demonstrate that magnetization can be reversed in a few hundreds of femtoseconds by overcoming the critical slowing down thanks to ultrafast spin cooling and spin heating mechanisms. We foresee that these results outline the potential of ultrafast spintronics for future ultrafast and energy efficient magnetic memory and storage devices. Furthermore, this should motivate further theoretical works in the field of femtosecond magnetization reversal., (© 2023. The Author(s).)

Introduction: Prior information in the realization of an invasive intervention is crucial. Indeed, the patient has to know theoretically his disease, diagnostic and therapeutic means, but also the risks of the used technique. The habits of information vary many from one center to another, in spite of the proposition of an information leaflet written by the French Society of Cardiology. Our aim was to evaluate the effectiveness of written information for patients hospitalized for coronary arteriography., Methods: Among patients hospitalized for realization of a programmed coronarography, a questionnaire was delivered before the information leaflet. The knowledge of the patients was so tested (27 items) before and after the reading of the information sheet (not limited time). The knowledge of the patients concerning coronarography indication, modalities, benefits, possible complications or still later possibilities was informed., Results: Thirty-four patients were included: all knew hospitalization reason, 86% were men, middle-aged 65 (IC 95% 60-70). Thirty-four percent (15-54) had studied in higher education. Ninety-seven percent had had information before. Only 56% (38-74) were informed about the mode of anesthesia, 36% (19-53) duration, 69% (53-86) the injection of iodine, 44% the risk of allergy, 53% the risk of bruise, 15% of the cardiac risks, 21% the renal risks. Seventy-one percent knew the diagnostic benefits, 44% the possible coronary angioplasty, 17% the eventuality of a bypass surgery. The delivery of the information leaflet did not modify the knowledge on most of these items, in particular the modalities and the profits. The risks were known significantly better for the allergy (P=0.019), the bruise (P=0.018), the cardiac risks (0.001)., Conclusions: The population benefiting from a coronarography considers to be enough informed. However, knowledge of the modalities, profits and risks is very low. The delivery of the consensual leaflet does not allow improving the situation, except as far as concerned the complications. Better information is so indispensable, not only to obtain a better support of the patient in the treatment, but also to prevent the forensic implications. The improvement of the information must be multifactorial, but usually used means could be not sufficient., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)