Publications

2023

• The Schottky barrier transistor in emerging electronic devices
  
  • Schwarz Mike
  • Vethaak Tom
  • Derycke Vincent
  • Francheteau Anaïs
  • Iniguez Benjamin
  • Kataria Satender
  • Kloes Alexander
  • Lefloch François
  • Lemme Max
  • Snyder John
  • Weber Walter Michael
  • Calvet Laurie
  Nanotechnology, Institute of Physics, 2023, 34, pp.352002. This paper explores how the Schottky barrier (SB) transistor is used in a variety of applications and material systems. A discussion of SB formation, current transport processes, and an overview of modeling are first considered. Three discussions follow, which detail the role of SB transistors in high performance, ubiquitous and cryogenic electronics. For high performance computing, the SB typically needs to be minimized to achieve optimal performance and we explore the methods adopted in carbon nanotube technology and two-dimensional electronics. On the contrary for ubiquitous electronics, the SB can be used advantageously in source-gated transistors and reconfigurable FETs for sensors, neuromorphic hardware and security applications. Similarly, judicious use of a SB can be an asset for applications involving Josephson junction FETs. (10.1088/1361-6528/acd05f)
  DOI : 10.1088/1361-6528/acd05f
• In situ study of chiral symmetry breaking in sodium chlorate solutions by Mueller matrix polarimetry
  
  • Arteaga Oriol
  • Arango-Restrepo Andrés
  • Barragán Daniel
  • Ossikovski Razvigor
  • Rubí Jose Miguel
  Chirality, Wiley, 2023, 35 (10), pp.700-707. Abstract This work presents a novel approach for investigating symmetry‐breaking processes during crystallization using Mueller matrix polarimetry. By applying this method to the cooling process of NaClO 3 solutions, we demonstrate its ability to capture not only the initial and final stages of crystallization but also the intermediate steps and dynamics of the process. This technique provides more comprehensive information and insights into the symmetry‐breaking mechanisms involved in crystal formation. Overall, this study highlights the potential of Mueller matrix polarimetry for in situ statistical measurements of the optical rotation and for monitoring the evolution of enantiomeric excesses. (10.1002/chir.23569)
  DOI : 10.1002/chir.23569
• Understanding LeTID degradation : a DFT study of point defects in silicon.
  
  • Tejeda Zacarias Elisa
  , 2023. Currently, the research and development of photovoltaic technologies that improve both their efficiency and production costs are priorities for the solar industry.In particular, a significant amount of research is focused on the aging mechanisms of solar panels, which have a major impact on their efficiency and durability. One of the causes of the decrease in performance of silicon-based panels is related to light and elevated temperature induced degradation (LeTID). This phenomenon appears after several months of use and can be responsible for a 16% reduction in cell efficiency. Although experimental studies show that various defects in silicon, such as hydrogen and metallic impurities, are involved in the mechanisms underlying LeTID, their contribution remains poorly understood,In this context, theoretical atomic methods, based on the first-principles of quantum mechanics calculations such as DFT, represent powerful tools to try to understand this degradation at the nanoscale levels. By analysing the stability and impact of hydrogen, silicon vacancies, siliconinterstitial silicon as well as metallic impurities (such as Ni and Co) on the properties of silicon, this study proposes a theoretical approach, based on the use of hybrid functionals, to model the precursor mechanisms of LeTID. It suggests that hydrogen-bonded impurities can act as recombination centres characterising LeTID.In addition, it is shown that interstitial hydrogen-bonded nickel and cobalt can induce LeTID, providing valuable insights into the dynamics of this type of aging. The approach proposed in this work offers the possibility to improve strategies for inhibiting this type of degradation and to identify the risks of LeTID under different operating conditions.
• Effects of formalin fixation on polarimetric properties of brain tissue: fresh or fixed?
  
  • Gros Romain
  • Rodríguez-Núñez Omar
  • Felger Leonard
  • Moriconi Stefano
  • Mckinley Richard
  • Pierangelo Angelo
  • Novikova Tatiana
  • Vassella Erik
  • Schucht Philippe
  • Hewer Ekkehard
  • Maragkou Theoni
  Neurophotonics, Society of Photo-optical Instrumentation Engineers (SPIE), 2023, 10 (02). (10.1117/1.NPh.10.2.025009)
  DOI : 10.1117/1.NPh.10.2.025009
• Intense pH Sensitivity Modulation in Carbon Nanotube-Based Field-Effect Transistor by Non-Covalent Polyfluorene Functionalization
  
  • Cho Gookbin
  • Grinenval Eva
  • Gabriel Jean-Christophe P.
  • Lebental Bérengère
  Nanomaterials, MDPI, 2023, 13 (7), pp.1157. We compare the pH sensing performance of non-functionalized carbon nanotubes (CNT) field-effect transistors (p-CNTFET) and CNTFET functionalized with a conjugated polyfluorene polymer (labeled FF-UR) bearing urea-based moieties (f-CNTFET). The devices are electrolyte-gated, PMMA-passivated, 5 µm-channel FETs with unsorted, inkjet-printed single-walled CNT. In phosphate (PBS) and borate (BBS) buffer solutions, the p-CNTFETs exhibit a p-type operation while f-CNTFETs exhibit p-type behavior in BBS and ambipolarity in PBS. The sensitivity to pH is evaluated by measuring the drain current at a gate and drain voltage of −0.8 V. In PBS, p-CNTFETs show a linear, reversible pH response between pH 3 and pH 9 with a sensitivity of 26 ± 2.2%/pH unit; while f-CNTFETs have a much stronger, reversible pH response (373%/pH unit), but only over the range of pH 7 to pH 9. In BBS, both p-CNTFET and f-CNTFET show a linear pH response between pH 5 and 9, with sensitivities of 56%/pH and 96%/pH, respectively. Analysis of the I–V curves as a function of pH suggests that the increased pH sensitivity of f-CNTFET is consistent with interactions of FF-UR with phosphate ions in PBS and boric acid in BBS, with the ratio and charge of the complexed species depending on pH. The complexation affects the efficiency of electrolyte gating and the surface charge around the CNT, both of which modify the I–V response of the CNTFET, leading to the observed current sensitivity as a function of pH. The performances of p-CNTFET in PBS are comparable to the best results in the literature, while the performances of the f-CNTFET far exceed the current state-of-the-art by a factor of four in BBS and more than 10 over a limited range of pH in BBS. This is the first time that a functionalization other than carboxylate moieties has significantly improved the state-of-the-art of pH sensing with CNTFET or CNT chemistors. On the other hand, this study also highlights the challenge of transferring this performance to a real water matrix, where many different species may compete for interactions with FF-UR. (10.3390/nano13071157)
  DOI : 10.3390/nano13071157
• Imagerie Microscopique Multimodale Polarimétrique Visible et Infrarouge Couplée à des Sources de Lumière Laser Accordable et Synchrotron
  
  • Albugami Bandar
  , 2023. Le microscope polarimétrique développé dans le cadre de cette thèse est le premier à combiner la possibilité de réaliser une analyse complète de la polarisation de la lumière avec une imagerie bimodale, dans les plans réel et de Fourier, sur un domaine spectral très large, du visible au moyen infrarouge. Développé en collaboration avec le Synchrotron SOLEIL, le microscope polarimétrique n’est pas un démonstrateur, mais un vrai instrument de recherche intégré au sein de la ligne de lumière synchrotron infrarouge SMIS, et mis au service de la communauté scientifique. Le développement instrumental a porté sur la conception optique et la conception polarimétrique. La conception optique a permis de créer le dispositif optique et mécanique qui constitue le microscope. La conception polarimétrique a permis de développer une configuration optique et un mode de pilotage novateurs du polarimètre, qui se distinguent par leur simplicité et leur efficacité. Ces caractéristiques donnent au polarimètre un avantage net par rapport à d’autres technologies, et permettent d’envisager une éventuelle exploitation commerciale. Une nouvelle méthode d’étalonnage polarimétrique, appelée la méthode du polariseur, initialement adapté pour le microscope polarimétrique s’avère aussi utile pour calibrer des polarimètres travaillant dans des domaines spectraux extrêmes pour lesquels peu solutions existent. Le microscope polarimétrique sera appliqué à l’étude tant de matériaux organiques qu’inorganiques d’origine naturelle ou artificielle. Le manuscrit termine par la description d’un exemple d’application consistant à l’étude de la réponse de feuilles de vigne et de ses composants par imagerie polarimétrique dans le visible et l’infrarouge. Les images dans le visible ont permis d’identifier la présence d’agrégats de cristallites nommées raphides, et les images infrarouges ont permis de déterminer leur composition chimique.
• Outdoor Performance Monitoring and Characterization of Novel Perovskite Solar Cells
  
  • Stéphan Emma
  • Migan-Dubois Anne
  • Parra Johanna
  • Chakar Joseph
  • Tondelier Denis
  • Narbey Stéphanie
  • Oswald Frédéric
  , 2023.
• Single‐Crystal Nanowire Cesium Tin Triiodide Perovskite Solar Cell
  
  • Dai Letian
  • Roca i Cabarrocas Pere
  • Ban Huaxia
  • Zhang Zhiguo
  • Sun Qiang
  • Li Xiongjie
  • Gu Anjie
  • Yang Wanpeng
  • Yu Haixuan
  • Shen Yan
  • Wang Mingkui
  Small, Wiley-VCH Verlag, 2023, 19 (22). Abstract This work reports for the first time a highly efficient single‐crystal cesium tin triiodide (CsSnI 3 ) perovskite nanowire solar cell. With a perfect lattice structure, low carrier trap density (≈5 × 10 10 cm −3 ), long carrier lifetime (46.7 ns), and excellent carrier mobility (>600 cm 2 V −1 s −1 ), single‐crystal CsSnI 3 perovskite nanowires enable a very attractive feature for flexible perovskite photovoltaics to power active micro‐scale electronic devices. Using CsSnI 3 single‐crystal nanowire in conjunction with highly conductive wide bandgap semiconductors as front‐surface‐field layers, an unprecedented efficiency of 11.7% under AM 1.5G illumination is achieved. This work demonstrates the feasibility of all‐inorganic tin‐based perovskite solar cells via crystallinity and device‐structure improvement for the high‐performance, and thus paves the way for the energy supply to flexible wearable devices in the future. (10.1002/smll.202208062)
  DOI : 10.1002/smll.202208062
• Recent Research Progress in Indophenine-Based-Functional Materials: Design, Synthesis, and Optoelectronic Applications
  
  • Ren Shiwei
  • Yassar Abderrahim
  Materials, MDPI, 2023, 16 (6), pp.2474. This review highlights selected examples, published in the last three to four years, of recent advance in the design, synthesis, properties, and device performance of quinoidal π-conjugated materials. A particular emphasis is placed on emerging materials, such as indophenine dyes that have the potential to enable high-performance devices. We specifically discuss the recent advances and design guidelines of π-conjugated quinoidal molecules from a chemical standpoint. To the best of the authors’ knowledge, this review is the first compilation of literature on indophenine-based semiconducting materials covering their scope, limitations, and applications. In the first section, we briefly introduce some of the organic electronic devices that are the basic building blocks for certain applications involving organic semiconductors (OSCs). We introduce the definition of key performance parameters of three organic devices: organic field effect transistors (OFET), organic photovoltaics (OPV), and organic thermoelectric generators (TE). In section two, we review recent progress towards the synthesis of quinoidal semiconducting materials. Our focus will be on indophenine family that has never been reviewed. We discuss the relationship between structural properties and energy levels in this family of molecules. The last section reports the effect of structural modifications on the performance of devices: OFET, OPV and TE. In this review, we provide a general insight into the association between the molecular structure and electronic properties in quinoidal materials, encompassing both small molecules and polymers. We also believe that this review offers benefits to the organic electronics and photovoltaic communities, by shedding light on current trends in the synthesis and progression of promising novel building blocks. This can provide guidance for synthesizing new generations of quinoidal or diradical materials with tunable optoelectronic properties and more outstanding charge carrier mobility. (10.3390/ma16062474)
  DOI : 10.3390/ma16062474
• Impact of Charge Carrier Injection/Extraction Performances in Low‐Dimension PEDOT:PSS Organic Electrochemical Transistors
  
  • Sych Galyna
  • Rannou Patrice
  • Jullien-Palletier Maxime
  • Sadki Saïd
  • Bonnassieux Yvan
  • Sanaur Sébastien
  Advanced Electronic Materials, Wiley, 2023, 9 (3), pp.2201067. (10.1002/aelm.202201067)
  DOI : 10.1002/aelm.202201067
• How Much Information Can We Extract From Photovoltaic Data? A Bayesian Optimization Approach to Determine Solar Cell Parameters and Degradation Rates From Power Production Data
  
  • Chakar Joseph
  • Calin Jean-Paul
  • Pavlov Marko
  • Puel Jean Baptiste
  • Bonnassieux Yvan
  , 2023.
• Depolarizing metrics in the biomedical field: Vision enhancement and classification of biological tissues
  
  • Canabal-Carbia Mónica
  • van Eeckhout Albert
  • Rodríguez Carla
  • González-Arnay Emilio
  • Estévez Irene
  • Gil José
  • Garcia-Caurel Enrique
  • Ossikovski Razvigor
  • Campos Juan
  • Lizana Angel
  Journal of Innovative Optical Health Sciences, 2023, 16 (05). Polarimetry encompasses a collection of optical techniques broadly used in a variety of fields. Nowadays, such techniques have provided their suitability in the biomedical field through the study of the polarimetric response of biological samples (retardance, dichroism and depolarization) by measuring certain polarimetric observables. One of these features, depolarization, is mainly produced by scattering on samples, which is a predominant effect in turbid media as biological tissues. In turn, retardance and dichroic effects are produced by tissue anisotropies and can lead to depolarization too. Since depolarization is a predominant effect in tissue samples, we focus on studying different depolarization metrics for biomedical applications. We report the suitability of a set of depolarizing observables, the indices of polarimetric purity (IPPs), for biological tissue inspection. We review some results where we demonstrate that IPPs lead to better performance than the depolarization index, which is a well-established and commonly used depolarization observable in the literature. We also provide how IPPs are able to significantly enhance contrast between different tissue structures and even to reveal structures hidden by using standard intensity images. Finally, we also explore the classificatory potential of IPPs and other depolarizing observables for the discrimination of different tissues obtained from ex vivo chicken samples (muscle, tendon, myotendinous junction and bone), reaching accurate models for tissue classification. (10.1142/S1793545823300045)
  DOI : 10.1142/S1793545823300045
• One-step synthesis of CuxOy/TiO2 photocatalysts by laser pyrolysis for selective ethylene production from propionic acid degradation
  
  • Karpiel Juliette
  • Lonchambon Pierre
  • Dappozze Frédéric
  • Florea Ileana
  • Dragoe Diana
  • Guillard Chantal
  • Herlin-Boime Nathalie
  Nanomaterials, MDPI, 2023, 13 (5), pp.792. In an effort to produce alkenes in an energy-saving way, this study presents for the first time a photocatalytic process that allows obtaining ethylene with high selectivity from propionic acid (PA) degradation. To this end, TiO2 nanoparticles (NPs) modified with copper oxides (CuxOy/TiO2) were synthetized by laser pyrolysis. The atmosphere of synthesis (He or Ar) strongly affects the morphology of photocatalysts and therefore their selectivity towards hydrocarbons (C2H4, C2H6, C4H10) and H2 products. Specifically, CuxOy/TiO2 elaborated under He environment presents highly dispersed copper species and favors the production of C2H6 and H2. On the contrary, CuxOy/TiO2 synthetized under Ar involves copper oxides organized into distinct NPs of ~2 nm diameter and promotes C2H4 as the major hydrocarbon product, with a selectivity i.e. C2H4/CO2 as high as 85% versus 1% obtained with pure TiO2. (10.3390/nano13050792)
  DOI : 10.3390/nano13050792
• Tailoring chiral optical properties by femtosecond laser direct writing in silica
  
  • Lu Jiafeng
  • Tian Jing
  • Poumellec Bertrand
  • Garcia-Caurel Enrique
  • Ossikovski Razvigor
  • Zeng Xianglong
  • Lancry Matthieu
  Light: Science and Applications, Nature Publishing Group, 2023, 12. An object that possesses chirality, that is, having its mirror image not overlayed on itself by rotation and translation, can provide a different optical response to a left-or right-handed circular polarized light. Chiral nanostructures may exhibit polarization-selective optical properties that can be controlled for micro-to-nano optical element engineering. An attractive way to induce such complex nanostructures in three-dimension in glass is femtosecond laser direct writing. However, the mechanism of femtosecond laser induced chirality remains to be unveiled due to complex physical and chemical processes occurring during the ultrashort light-matter interaction. Here, a phenomenological model is proposed and is built on two-layers phase shifters to account for this laser-induced optical chirality in an initially achiral material (silica glass). This model is based on the observation that femtosecond laser induced nanogratings own two principal contributions to its aggregate birefringent response: a form and a stress-related one. By refining this formalism, a multilayer approach is developed to imprint on demand optical rotation. Values up to +/-60°at 550 nm within an optimal 80 μm thickness in silica glass are possible, corresponding to the highest value in a glass to date. These results provide new insights of circular-optical control in micro-nano optical manufacturing and open new opportunities for photonics applications. (10.1038/s41377-023-01080-y)
  DOI : 10.1038/s41377-023-01080-y
• Reaching the 5% theoretical limit of fluorescent OLEDs with push-pull benzophospholes
  
  • Ledos Nicolas
  • Tondelier Denis
  • Geffroy Bernard
  • Jacquemin Denis
  • Bouit Pierre-Antoine
  • Hissler Muriel
  Journal of Materials Chemistry C, Royal Society of Chemistry, 2023, 11, pp.3826-3831. We report the synthesis and characterization of benzophosphole oxides featuring an ethoxy substituent on the P atom and electro-donating amino groups on the lateral phenyl groups. The optical and redox properties of these compounds are studied experimentally and computationally (TD-DFT). In particular, we show how the nature of the donor allows fine-tuning the internal charge transfer (ICT) and, thus, the optical properties. Considering the intense fluorescence in the solid state (powder or thin film) and the favorable redox and thermal properties, these compounds were introduced in multilayered organic light emitting devices. All compounds display high efficiency and one compound even exhibits an external quantum efficiency (EQE) of 5%, which represents the theoretical limit of the EQE of purely fluorescent emitters. These results highlight the potential of this novel family of fluorophores to develop next generation optoelectronic/photonic devices. (10.1039/D3TC00245D)
  DOI : 10.1039/D3TC00245D
• Solution-Processed Functionalized Graphene Film Prepared by Vacuum Filtration for Flexible NO2 Sensors
  
  • Dieng Mbaye
  • Sankar Siva
  • Ni Pingping
  • Florea Ileana
  • Alpuim Pedro
  • Capasso Andrea
  • Yassar Abderrahim
  • Bouanis Fatima Zahra
  Sensors, MDPI, 2023, 23 (4), pp.1831. Large-scale production of graphene nanosheets (GNSs) has led to the availability of solution-processable GNSs on the commercial scale. The controlled vacuum filtration method is a scalable process for the preparation of wafer-scale films of GNSs, which can be used for gas sensing applications. Here, we demonstrate the use of this deposition method to produce functional gas sensors, using a chemiresistor structure from GNS solution-based techniques. The GNS suspension was prepared by liquid-phase exfoliation (LPE) and transferred to a polyvinylidene fluoride (PVDF) membrane. The effect of non-covalent functionalization with Co-porphyrin and Fe-phthalocyanines on the sensor properties was studied. The pristine and functionalized GNS films were characterized using different techniques such as Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and electrical characterizations. The morphological and spectroscopic analyses both confirm that the molecules (Co-porphyrin and Fe-phthalocyanine) were successfully adsorbed onto the GNSs surface through π-π interactions. The chemiresistive sensor response of functionalized GNSs toward the low concentrations of nitrogen dioxide (NO2) (0.5–2 ppm) was studied and compared with those of the film of pristine GNSs. The tests on the sensing performance clearly showed sensitivity to a low concentration of NO2 (5 ppm). Furthermore, the chemical modification of GNSs significantly improves NO2 sensing performance compared to the pristine GNSs. The sensor response can be modulated by the type of adsorbed molecules. Indeed, Co-Por exhibited negative responsiveness (the response of Co-Por-GNS sensors and pristine GNS devices was 13.1% and 15.6%, respectively, after exposure to 0.5 ppm of NO2). Meanwhile, Fe-Phc-GNSs induced the opposite behavior resulting in an increase in the sensor response (the sensitivity was 8.3% and 7.8% of Fe-Phc-GNSs and pristine GNSs, respectively, at 0.5 ppm NO2 gas). (10.3390/s23041831)
  DOI : 10.3390/s23041831
• Editorial: Optical imaging and laser technologies in neuro-oncology
  
  • Yashin Konstantin
  • Novikova Tatiana
  • Shcheslavskiy Vladislav
  Frontiers in Oncology, Frontiers Media, 2023, 12. (10.3389/fonc.2022.1103711)
  DOI : 10.3389/fonc.2022.1103711
• In situ minority carrier lifetime via fast modulated photoluminescence
  
  • Poplawski Mateusz
  • Silva François
  • Vanel Jean-Charles
  • Roca i Cabarrocas Pere
  EPJ Photovoltaics, EDP sciences, 2023, 14, pp.19. Modulated photoluminescence (MPL) is a powerful technique for determining the effective minority carrier lifetime (τeff) of semiconductor materials and devices. MPL is based on the measurement of phase shifts between two sinusoidal waves (minimal amplitude excitation; and PL signal). In particular, in situ τeff has been proven to be an effective measurement at showing changes within a plasma-enhanced chemical vapor deposition reactor during fabrication of c-Si solar cells. However, the required time for a single measurement, using the previous method, was 40 s. In this paper a new input signal is proposed, called Dolphin's Wave, providing a method for decreasing the required measurement period to under 2 s, using superposition, frequency sweeps, and wavelets. (10.1051/epjpv/2023010)
  DOI : 10.1051/epjpv/2023010
• Impact of corpus callosum fiber tract crossing on polarimetric images of human brain histological sections: ex vivo studies in transmission configuration
  
  • Ivanov Deyan
  • Si Lu
  • Felger Leonard
  • Maragkou Theoni
  • Schucht Philippe
  • Schanne-Klein Marie-Claire
  • Ma Hui
  • Ossikovski Razvigor
  • Novikova Tatiana
  Journal of Biomedical Optics, Society of Photo-optical Instrumentation Engineers, 2023, 28 (10), pp.102908. Significance: Imaging Mueller polarimetry is capable to trace in-plane orientation of brain fiber tracts by detecting the optical anisotropy of white matter of healthy brain. Brain tumor cells grow chaotically and destroy this anisotropy. Hence, the drop in scalar retardance values and randomization of the azimuth of the optical axis could serve as the optical marker for brain tumor zone delineation. Aim: The presence of underlying crossing fibers can also affect the values of scalar retardance and the azimuth of the optical axis. We studied and analyzed the impact of fiber crossing on the polarimetric images of thin histological sections of brain corpus callosum. Approach: We used the transmission Mueller microscope for imaging of two-layered stacks of thin sections of corpus callosum tissue to mimic the overlapping brain fiber tracts with different fiber orientations. The decomposition of the measured Mueller matrices was performed with differential and Lu–Chipman algorithms and completed by the statistical analysis of the maps of scalar retardance, azimuth of the optical axis, and depolarization. Results: Our results indicate the sensitivity of Mueller polarimetry to different spatial arrangement of brain fiber tracts as seen in the maps of scalar retardance and azimuth of optical axis of two-layered stacks of corpus callosum sections The depolarization varies slightly (<15 % ) with the orientation of the optical axes in both corpus callosum stripes, but its value increases by 2.5 to 3 times with the stack thickness. Conclusions: The crossing brain fiber tracts measured in transmission induce the drop in values of scalar retardance and randomization of the azimuth of the optical axis at optical path length of 15 μm. It suggests that the presence of nerve fibers crossing within the depth of few microns will be also detected in polarimetric maps of brain white matter measured in reflection configuration. (10.1117/1.JBO.28.10.102908)
  DOI : 10.1117/1.JBO.28.10.102908
• [4]-Cyclo-2,7-carbazole as host material in high-efficiency phosphorescent OLEDs: A new perspective for nanohoops in organic electronics
  
  • Brouillac Clement
  • Lucas Fabien
  • Tondelier Denis
  • Rault-Berthelot Joëlle
  • Lebreton Christophe
  • Jacques Emmanuel
  • Quinton Cassandre
  • Poriel Cyril
  Advanced Optical Materials, 2023. (10.1002/adom.202202191)
  DOI : 10.1002/adom.202202191
• Effects of an epitaxial graphene layer for the growth of nickel silicides on a Ni(111) substrate
  
  • Ronci Fabio
  • Colonna Stefano
  • Flammini Roberto
  • de Crescenzi Maurizio
  • Scarselli Manuela
  • Salvato Matteo
  • Berbezier Isabelle
  • Vach Holger
  • Castrucci Paola
  Applied Surface Science, Elsevier, 2023, 611, pp.155763. In this paper, we report on an in-depth study on the growth of nickel silicides, either on a clean Ni(111) substrate or in the presence of a previously-grown epitaxial single graphene (Gr) layer, by means of Auger electron spectroscopy (AES), low energy electron diffraction (LEED), and scanning tunneling microscopy (STM). We demonstrate that two different nickel silicides, namely Ni3Si and Ni2Si, progressively form as the annealing temperature is increased from 450 ◦C to 600 ◦C. The presence of the Gr layer does not change the nature of the two silicide phases but rather affects the morphology of the silicide overlayer. Indeed, in the presence of Gr, the deposited silicon atoms intercalate by passing through the Gr defects or domain boundaries and accumulate on specific sample areas, resulting in the formation of multilayer silicide islands. In the absence of Gr, the deposited silicon atoms react uniformly with the nickel substrate, resulting in the formation of homogeneous large scale silicide layers. (10.1016/j.apsusc.2022.155763)
  DOI : 10.1016/j.apsusc.2022.155763
• 3D structured Bessel beam polarization and its application to imprint chiral optical properties in silica
  
  • Lu Jiafeng
  • Hassan Mostafa
  • Courvoisier François
  • Garcia-Caurel Enrique
  • Brisset François
  • Ossikovski Razvigor
  • Zeng Xianglong
  • Poumellec Bertrand
  • Lancry Matthieu
  APL Photonics, AIP Publishing LLC, 2023, 8, pp.060801 (1-10). Polarization plays a crucial role in light–matter interactions; hence its overall manipulation is an essential key to unlock the versatility of light manufacturing, especially in femtosecond laser direct writing. Existing polarization-shaping techniques, however, only focus on their manipulation in the transverse plane of light beams, i.e., two-dimensional control. In this paper, we propose a novel passive strategy that exploits a class of femtosecond laser written space varying birefringent elements to shape the polarization state along the optical path. As a demonstration, we generate a three-dimensional structured Bessel beam whose linear polarization state slowly evolves along the focus (typ. 90° within 60λ). Such a “helically polarized” Bessel beam allows imprinting “twisted nanogratings” in SiO<sub&gt2</sub&gt glass which result in an extrinsic optical chirality at a micrometric scale and own a high optical rotation. Our work provides new perspectives for three-dimensional polarization manipulation and insights into applications in structured light, light–matter interaction, and chiral device fabrication. (10.1063/5.0140843)
  DOI : 10.1063/5.0140843
• Large circular dichroism in the emission by an incandescent metasurface
  
  • Nguyen Anne
  • Hugonin Jean-Paul
  • Coutrot Anne-Lise
  • Garcia-Caurel Enrique
  • Vest Benjamin
  • Greffet Jean-Jacques
  Optica, Optical Society of America - OSA Publishing, 2023, 10 (2), pp.232-238. Compact sources in the mid-wave infrared (MWIR) are needed for several applications ranging from spectroscopy to free-space communication. Ultra-thin incandescent metasurfaces are promising candidates, offering the possibility of tuning the emission spectrum, directivity and modulation speed. However, control over polarization remains a challenge, especially when it comes to emission of circularly polarized light. Here, emission of polarized MWIR radiation by a 700 nm thick incandescent chiral metasurface is reported. The degree of polarization is above 0.5 with degree of circular polarization of 0.38 at 5 µm. The metasurface is heated by Joule effect and its emission can be modulated beyond 10 MHz. This paves the way to detection techniques using polarization as an additional degree of freedom. (10.1364/OPTICA.480292)
  DOI : 10.1364/OPTICA.480292
• Bimodal ionic photomemristor based on a high-temperature oxide superconductor/semiconductor junction
  
  • El Hage Ralph
  • Humbert Vincent
  • Rouco Victor
  • Sánchez-Santolino Gabriel
  • Lagarrigue Aurelien
  • Seurre Kevin
  • Carreira Santiago
  • Sander Anke
  • Charliac Jérôme
  • Mesoraca Salvatore
  • Trastoy Juan
  • Briatico Javier
  • Santamaría Jacobo
  • Villegas Javier
  Nature Communications, Nature Publishing Group, 2023, 14 (1), pp.3010. Abstract Memristors, a cornerstone for neuromorphic electronics, respond to the history of electrical stimuli by varying their electrical resistance across a continuum of states. Much effort has been recently devoted to developing an analogous response to optical excitation. Here we realize a novel tunnelling photo-memristor whose behaviour is bimodal: its resistance is determined by the dual electrical-optical history. This is obtained in a device of ultimate simplicity: an interface between a high-temperature superconductor and a transparent semiconductor. The exploited mechanism is a reversible nanoscale redox reaction between both materials, whose oxygen content determines the electron tunnelling rate across their interface. The redox reaction is optically driven via an interplay between electrochemistry, photovoltaic effects and photo-assisted ion migration. Besides their fundamental interest, the unveiled electro-optic memory effects have considerable technological potential. Especially in combination with high-temperature superconductivity which, in addition to facilitating low-dissipation connectivity, brings photo-memristive effects to the realm of superconducting electronics. (10.1038/s41467-023-38608-0)
  DOI : 10.1038/s41467-023-38608-0
• Polarized Light in Biomedical Imaging and Sensing
  
  • Ramella-Roman Jessica
  • Novikova Tatiana
  , 2023. (10.1007/978-3-031-04741-1)
  DOI : 10.1007/978-3-031-04741-1