Publications

2017

Influence of deposition rate on the structural properties of plasma-enhanced CVD epitaxial silicon
- Chen Wanghua
- Cariou Romain
- Hamon Gwenaëlle
- Léal Ronan
- Maurice Jean-Luc
- Cabarrocas Pere Roca I
Scientific Reports, Nature Publishing Group, 2017, 7 (1). (10.1038/srep43968)
DOI : 10.1038/srep43968
Negative Isotope Effect on Field-Effect Hole Transport in Fully Substituted 13 C-Rubrene
- Ren Xinglong
- Bruzek Matthew J
- Hanifi David A
- Schulzetenberg Aaron
- Wu Yanfei
- Kim Chang-Hyun
- Zhang Zhuoran
- Johns James E
- Salleo Alberto
- Fratini Simone
- Troisi Alessandro
- Douglas Christopher J
- Frisbie C. Daniel
Advanced Electronic Materials, Wiley, 2017, 3 (4), pp.1700018. have revealed the simultaneous presence of both high room temperature hole mobility above 10 cm 2 V −1 s −1[5] and, crucially , a negative temperature exponent for the mobility, i.e., mobility increases as temperature decreases down to about 180 K. [6] These observations and others, including mobility anisotropy [7,8] and a robust Hall effect, [9,10] are strong evidence for band-like transport in rubrene (band-width ≈0.5 eV), [11] where many features of classical band transport are observed. However, the estimated carrier mean free paths remain on the order of the unit cell dimension (≈1 nm), thus precluding the typical band picture in conventional semiconductors. The precise nature of band-like transport in organic semiconductor crystals is still being explored. [12] Currently, a consistent picture of charge transport in high mobility crystals is offered by the dynamic disorder model (DDM, also known as transient localization), in which the carrier transient localization length l loc and the propagation rate ω are determined by a competition between intermolecular electronic coupling and charge-phonon interaction ; in this scenario the carrier mobility μ can be evaluated as [13] µ ω = B loc 2 e k T l (1) Isotopic substitution is a useful method to study the influence of nuclear motion on the kinetics of charge transport in semiconductors. However, in organic semiconductors, no observable isotope effect on field-effect mobility has been reported. To understand the charge transport mechanism in rubrene, the benchmark organic semiconductor, crystals of fully isotopically substituted rubrene, 13 C-rubrene (13 C 42 H 28), are synthesized and characterized. Vapor-grown 13 C-rubrene single crystals have the same crystal structure and quality as native rubrene crystals (i.e., rubrene with a natural abundance of carbon isotopes). The characteristic transport signatures of rubrene, including room temperature hole mobility over 10 cm 2 V −1 s −1 , intrinsic band-like transport, and clear Hall behavior in the accumulation layer of air-gap transistors, are also observed for 13 C-rubrene crystals. The field-effect mobility distributions based on 74 rubrene and 13 C-rubrene devices, respectively, reveal that 13 C isotopic substitution produces a 13% reduction in the hole mobility of rubrene. The origin of the negative isotope effect is linked to the redshift of vibrational frequencies after 13 C-substitution, as demonstrated by computer simulations based on the transient localization (dynamic disorder) scenario. Overall, the data and analysis provide an important benchmark for ongoing efforts to understand transport in ordered organic semiconductors. (10.1002/aelm.201700018)
DOI : 10.1002/aelm.201700018
Etude de l'utilisation du ZnO comme contact de type n dans des dispositifs photovoltaïques à base de pérovskite hybride
- Hadouchi Warda
, 2017. Les cellules solaires pérovskites hybrides ont marqué le monde du photovoltaïque avec une augmentation spectaculaire des rendements durant ces quatre dernières années. Avec des rendements dépassant 20% à l’heure actuelle, ce type de cellules suscite une attention particulière dans le monde scientifique. Dans l’architecture de la cellule solaire pérovskite, le TiO2 est l’oxyde le plus utilisé comme matériau collecteur d’électrons. Cette couche d’oxyde joue un rôle important dans la cellule, cependant le procédé d’élaboration du TiO2 requiert une étape de recuit à haute température. En plus des coûts élevés de production qu’elle implique, son utilisation exclut son application aux substrats sensibles aux hautes températures tels que les substrats plastiques flexibles par exemple.Cette thèse est centrée sur le remplacement du TiO2 par le ZnO en tant que couche collectrice d’électrons et bloqueuse de trous. Ce matériau représente une alternative intéressante en raison de ces propriétés comparables et même supérieures à celles du TiO2. L’intérêt du choix du ZnO réside dans sa simplicité de mise en œuvre. Ce matériau peut en effet être synthétisé à basse température (<100°C) et sous différentes structures. Dans cette étude nous avons fait le choix de considérer les croissances de ZnO par voie électrochimique et par pulvérisation cathodique. Dans des conditions de dépôts optimisées des couches de pérovskite et de ZnO, des rendements record de 14.2% et 9.7% ont été obtenus dans des architectures plane et nanostructurée respectivement.
Surface potential investigation on interdigitated back contact solar cells by Scanning Electron Microscopy and Kelvin Probe Force Microscopy: Effect of electrical bias
- Narchi Paul
- Neplokh Vladimir
- Piazza Valerio
- Bearda Twan
- Bayle Fabien
- Foldyna Martin
- Toccafondi Chiara
- Prod’homme Patricia
- Tchernycheva Maria
- Roca I Cabarrocas Pere
Solar Energy Materials and Solar Cells, Elsevier, 2017, 161, pp.263 - 269. (10.1016/j.solmat.2016.12.009)
DOI : 10.1016/j.solmat.2016.12.009
Direct experimental evidence of ionic migration in halide perovskite films by GDOES measurements
- Lee Heejae
- Lee Heeryung
- Marronnier Arthur
- Tondelier Denis
- Gaiaschi Sophia
- Chapon Patrick
- Bonnassieux Yvan
- Geffroy Bernard
, 2017. In recent years, halide perovskite solar cells (PSCs) have been studied steadily due to their potential properties: high power conversion efficiency (PCE) to over 21% and low processing cost. However, the stability of PSCs under operating conditions is the main challenge to be addressed before commercialization. It has been suggested that ionic migration could impact optoelectronic performance and affect device operation and long-term stability [3]. In this study, glow-discharge optical emission spectroscopy (GDOES) is used to analyze the depth profiles of constituent elements in halide perovskite films with applied voltage. Solar cells based on halide perovskite (CH$_3$NH$_3$PbI$_3$-XClX) are fabricated by one-step solution-process with PCE of 12.7% (active area of 0.28 cm2) and short-circuit current density (Jsc) of 21.9 mA/cm$^2$. A shift of iodide and chloride ions distribution in perovskite films is observed depending on applied voltage. In this communication, it is shown that GDOES is a powerful method to investigate ionic migration in PSCs under operating conditions.
Traduire la Physique
- Suchet Daniel
Écritures, Centre de Recherches Italiennes - Université Paris Nanterre (CRIX EA 369 Études Romanes), 2017, 9. De la physique à la traduction l'écart peut sembler grand. Néanmoins, le physicien navigue entre trois mondes, qu'il imagine souvent séparés par des frontières bien définies : le monde réel, celui des phénomènes naturels qui constituent ses objets d'étude – le monde mathématique, dans lequel il est armés d'outils théo-riques – et la société humaine, vers laquelle tendent ses efforts de diffusion de la connaissance. Réfléchir à la traduction offre un éclairage particulier sur les interactions et la hiérarchisation implicite que nous adoptons entre ces mondes et permet d'interroger des frontières que nous avons tendance à prendre pour évidentes.
Electron-Rich 4-Substituted Spirobifluorenes: Toward a New Family of High Triplet Energy Host Materials for High-Efficiency Green and Sky Blue Phosphorescent OLEDs
- Quinton Cassandre
- Thiery Sébastien
- Jeannin Olivier
- Tondelier Denis
- Geffroy Bernard
- Jacques Emmanuel
- Rault-Berthelot Joëlle
- Poriel Cyril
ACS Applied Materials & Interfaces, Washington, D.C. : American Chemical Society, 2017, 9 (7), pp.6194-6206. We report herein a detailed structure-properties relationship study of the first examples of electron-rich 4-substituted spirobifluorenes for organic electronic applications, namely, 4-phenyl-N-carbazole-spirobifluorene (4-PhCz-SBF) and 4-(3,4,5-trimethoxyphenyl)-spirobifluorene (4-Ph(OMe)-SBF). The incorporation of the electron-rich moieties in the ortho position of the biphenyl linkage (position C4) induces unique properties, very different from those previously described in the literature for this family of semiconductors. Both dyes can be readily synthesized, possess high triplet energies and excellent thermal stability, and their HOMO energy levels are highly increased compared to those of other 4-substituted SBFs. We also provide in this work the first rationalization of the peculiar fluorescence of 4-substituted SBFs. Finally, the present dyes have been successfully incorporated as host in green and blue phosphorescent organic light-emitting diodes with high performance either for the green (EQE of 20.2%) or the blue color (EQE of 9.6%). These performances are, to the best of our knowledge, among the highest reported to date for 4-substituted SBF derivatives. (10.1021/acsami.6b14285)
DOI : 10.1021/acsami.6b14285
Thiophene vs thiazole: Effect of the π-connector on the properties of phthalimide end-capped diketopyrrolopyrrole based molecular acceptors for organic photovoltaics
- Josse Pierre
- Chávez Patricia
- Dindault Chloé
- Dalinot Clément
- Mcafee Seth
- Dabos-Seignon Sylvie
- Tondelier Denis
- Welch Gregory
- Blanchard Philippe
- Leclerc Nicolas
- Cabanetos Clément
Dyes and Pigments, Elsevier, 2017, 137, pp.576-583. (10.1016/j.dyepig.2016.10.046)
DOI : 10.1016/j.dyepig.2016.10.046
Characteristics of a learning environment to support prospective secondary mathematics teachers' noticing of students' thinking related to the limit concept
- Fernandez C.
- Llinares S
- Callejo M L
- Moreno M.
- Sánchez-Matamoros Gloria
, 2017. The aim of this study is to describe changes in the way that prospective secondary school teachers notice students' mathematical thinking related to the limit concept in a learning environment designed ad hoc. The learning environment progressively nests the skills of attending to, interpreting and deciding as three interrelated skills of professional noticing. Results show characteristics of how prospective teachers gained expertise in the three skills since four out of five groups of prospective teachers interpreted students' mathematical reasoning attending to the mathematical elements of the dynamic conception of limit. The links between attending to and interpreting helped prospective teachers justify the teaching activities proposed to support the progression of students' mathematical reasoning: from a mathematical point of view or considering mathematical cognitive processes involved.
Optical biopsy of tissue with Mueller polarimetry: theory and experiments (Conference Presentation)
- Novikova Tatiana
- Meglinski Igor
- Garcia-Caurel Enric
- Bykov Alexander
- Rehbinder Jean
- Deby Stanislas
- Vizet Jérémy
- Pierangelo Angelo
- Moreau François
- Validire Pierre
- Benali Abdelali
- Gayet Brice
- Teig Benjamin
- Nazac André
- Ossikovski Razvigor
, 2017, pp.29. (10.1117/12.2253123)
DOI : 10.1117/12.2253123
Spirobifluorene based small push-pull molecules for organic photovoltaic applications
- Dalinot Clément
- Szalóki György
- Dindault Chloé
- Segut Olivier
- Sanguinet Lionel
- Leriche Philippe
Dyes and Pigments, Elsevier, 2017, 140, pp.62-69. Four analogous push-pull systems have been synthesized. If the latter all involve the same electron rich diphenylamine termination (D) and π-conjugating spacer (p) they differ from their electron withdrawing groups (A) and more importantly by their linear or 3D structure. Indeed, two push-pull spirobifluorene derivatives, which present two perpendicular D-p-A systems by molecule, are compared to their linear analogues. After description of their syntheses, spectroscopic and electrochemical properties, comforted by theoretical calculations, are discussed and compared. Then, a preliminary evaluation of compounds as active materials in organic solar cells is presented and demonstrates the potential interest of spiro-based derivatives for organic photovoltaics. (10.1016/j.dyepig.2017.01.034)
DOI : 10.1016/j.dyepig.2017.01.034
Direct Piezoelectric Coefficient Measurements of PVDF and PLLA under Controlled Strain and Stress
- Bernard Francois
- Gimeno Leticia
- Viala Bernard
- Gusarov Boris
- Cugat Orphée
, 2017, 1, pp.335.
Optical techniques for cervical neoplasia detection
- Novikova Tatiana
Beilstein Journal of Nanotechnology, Karlsruhe Institute of Technology., 2017, 8, pp.1844-1862. This paper provides an overview of the current research in the field of optical techniques for cervical neoplasia detection and covers a wide range of the existing and emerging technologies. Using colposcopy, a visual inspection of the uterine cervix with a colposcope (a binocular microscope with 3- to 15-fold magnification), has proven to be an efficient approach for the detection of invasive cancer. Nevertheless, the development of a reliable and cost-effective technique for the identification of precancerous lesions, confined to the epithelium (cervical intraepithelial neoplasia) still remains a challenging problem. It is known that even at early stages the neoplastic transformations of cervical tissue induce complex changes and modify both structural and biochemical properties of tissues. The different methods, including spectroscopic (diffuse reflectance spectroscopy, induced fluorescence and autofluorescence spectroscopy, Raman spectroscopy) and imaging techniques (confocal microscopy, optical coherence tomography, Mueller matrix imaging polarimetry, photoacoustic imaging), probe different tissue properties that may serve as optical biomarkers for diagnosis. Both the advantages and drawbacks of these techniques for the diagnosis of cervical precancerous lesions are discussed and compared. (10.3762/bjnano.8.186)
DOI : 10.3762/bjnano.8.186
Tasked-based quantification of measurement utility for ex vivo multi-spectral Mueller polarimetry of the uterine cervix
- Kupinski Meredith
- Rehbinder Jean
- Haddad Huda
- Deby Stanislas
- Vizet Jeremy
- Pierangelo Angelo
- Teig Benjamin
- Nazac André
- Moreau François
- Novikova Tatiana
, 2017, 104110N.
FR 1753131 - Capteurs chimiques à base de nanotubes de carbone fonctionnalisés par des polymères conjugués pour l'analyse en milieu aqueux
- Zucchi Gaël
- Lebental Bérengère
- Loisel Loic
- Ramachandran Sasikumar
- Flores Guttierez Alfredo
- Wang Xin Yang
- Godumala Mallesham
- Bodelot Laurence
, 2017, pp.42p. La présente invention concerne la détection, l'identification et la quantification sélective d'espèces chimiques ioniques dans un fluide, typiquement en phase aqueuse. La présente invention concerne plus particulièrement un capteur chimique miniature destiné notamment à l'analyse de solutions aqueuses. Le capteur comprend des nanotubes de carbone fonctionnalisés en surface par des polymères conjugués porteurs de groupements chimiques appropriés et permettant une telle détection, identification et quantification. Le procédé de préparation et les utilisations du capteur sont décrits.
Synthesis engineering of iron oxide raspberry-shaped nanostructures
- Gerber O.
- Pichon B.
- Ihiawakrim D.
- Florea I.
- Moldovan S.
- Ersen O.
- Bégin D.
- Greneche Jean-Marc
- Lemonnier S.
- Barraud E.
- Bégin S.
Nanoscale, Royal Society of Chemistry, 2017, 9 (1), pp.305-313. Magnetic porous nanostructures consisting of oriented aggregates of iron oxide nanocrystals display very interesting properties such as a lower oxidation state of magnetite, and enhanced saturation magnetization in comparison with individual nanoparticles of similar sizes and porosity. However, the formation mechanism of these promising nanostructures is not well understood, which hampers the fine tuning of their magnetic properties, for instance by doping them with other elements. Therefore the formation mechanism of porous raspberry shaped nanostructures (RSNs) synthesized by a one-pot polyol solvothermal method has been investigated in detail from the early stages by using a wide panel of characterization techniques, and especially by performing original in situ HR-TEM studies in temperature. A time-resolved study showed the intermediate formation of an amorphous iron alkoxide phase with a plate-like lamellar structure (PLS). Then, the fine investigation of PLS transformation upon heating up to 500 °C confirmed that the synthesis of RSNs involves two iron precursors: the starting one (hydrated iron chlorides) and the in situ formed iron alkoxide precursor which decomposes with time and heating and contributes to the growth step of nanostructures. Such an understanding of the formation mechanism of RSNs is necessary to envision efficient and rational enhancement of their magnetic properties. (10.1039/c6nr07567c)
DOI : 10.1039/c6nr07567c
Natural occurrence of the diamond hexagonal structure in silicon nanowires grown by a plasma-assisted vapour-liquid-solid method
- Tang J.
- J.L. Maurice
- Fossard F.
- Florea I.
- W. Chen
- E.V. Johnson
- Foldyna M.
- L. Yu
- Roca I Cabarrocas P.
Nanoscale, Royal Society of Chemistry, 2017, 9 (24), pp.8113-8118. Silicon nanowires have been grown by a plasma-assisted vapour–liquid–solid method using tin as the catalyst. Transmission electron microscopy in the [1-210] zone axis shows that the diamond hexagonal (P63/mmc) crystal structure is present in several nanowires. This is the first unambiguous proof of the natural occurrence of this metastable phase to our knowledge. (10.1039/c7nr01299c)
DOI : 10.1039/c7nr01299c
Optical techniques for cervical neoplasia detection
- Novikova Tatiana
Beilstein Journal of Nanotechnology, Karlsruhe Institute of Technology., 2017, 8, pp.1844-1862. This paper provides an overview of the current research in the field of optical techniques for cervical neoplasia detection and covers a wide range of the existing and emerging technologies. Using colposcopy, a visual inspection of the uterine cervix with a colposcope (a binocular microscope with 3- to 15-fold magnification), has proven to be an efficient approach for the detection of invasive cancer. Nevertheless, the development of a reliable and cost-effective technique for the identification of precancerous lesions, confined to the epithelium (cervical intraepithelial neoplasia) still remains a challenging problem. It is known that even at early stages the neoplastic transformations of cervical tissue induce complex changes and modify both structural and biochemical properties of tissues. The different methods, including spectroscopic (diffuse reflectance spectroscopy, induced fluorescence and autofluorescence spectroscopy, Raman spectroscopy) and imaging techniques (confocal microscopy, optical coherence tomography, Mueller matrix imaging polarimetry, photoacoustic imaging), probe different tissue properties that may serve as optical biomarkers for diagnosis. Both the advantages and drawbacks of these techniques for the diagnosis of cervical precancerous lesions are discussed and compared. (10.3762/bjnano.8.186)
DOI : 10.3762/bjnano.8.186
Radiation Experiments on a 28nm Single-Chip Many-core Processor and SEU error-rate prediction
- Vargas Vanessa
- Ramos Pablo
- Ray Vincent
- Jalier Camille
- Stevens Renaud
- Dupont de Dinechin Benoît
- Baylac Maud
- Villa Francesca
- Rey Solenne
- Zergainoh Nacer-Eddine
- Méhaut Jean-François
- Velazco Raoul
IEEE Transactions on Nuclear Science, Institute of Electrical and Electronics Engineers, 2017, 64 (1), pp.483-490. This work evaluates the SEE static and dynamic sensitivity of a single-chip many-core processor having implemented 16 compute clusters, each one with 16 processing cores. The SEU error-rate of an application implemented in the device is predicted by combining experimental results with those issued from fault injection campaigns applying the CEU (Code Emulating Upsets) approach. In addition, a comparison of the dynamic tests when processing-cores cache memories are enabled and disabled is presented. The experiments were validated through radiation ground testing performed with 14 MeV neutrons on the MPPA- 256 many-core processor manufactured in TSMC CMOS 28HP technology. An analysis of the erroneous results in processor GPRs was carried-out in order to explain their possible causes. (10.1109/TNS.2016.2638081)
DOI : 10.1109/TNS.2016.2638081
Power coupling mode transitions induced by tailored voltage waveforms in capacitive oxygen discharges
- Derzsi A.
- Bruneau Bastien
- Gibson Andrew
- Johnson Erik
- O'Connell D.
- Gans T.
- Booth Jean-Paul
- Donko Zoltan
Plasma Sources Science and Technology, IOP Publishing, 2017, 26 (3), pp.034002. Low-pressure capacitively coupled radio frequency discharges operated in O 2 and driven by tailored voltage waveforms are investigated experimentally and by means of kinetic simulations. Pulse-type (peaks/valleys) and sawtooth-type voltage waveforms that consist of up to four consecutive harmonics of the fundamental frequency are used to study the amplitude asymmetry effect as well as the slope asymmetry effect at different fundamental frequencies (5, 10, and 15 MHz) and at different pressures (50?700 mTorr). Values of the DC self-bias determined experimentally and spatio-temporal excitation rates derived from phase resolved optical emission spectroscopy measurements are compared with particle-in-cell/Monte Carlo collisions simulations. The spatio-temporal distributions of the excitation rate obtained from experiments are well reproduced by the simulations. Transitions of the discharge electron heating mode from the drift-ambipolar mode to the ? -mode are induced by changing the number of consecutive harmonics included in the driving voltage waveform or by changing the gas pressure. Changing the number of harmonics in the waveform has a strong effect on the electronegativity of the discharge, on the generation of the DC self-bias and on the control of ion properties at the electrodes, both for pulse-type, as well as sawtooth-type driving voltage waveforms The effect of the surface quenching rate of oxygen singlet delta metastable molecules on the spatio-temporal excitation patterns is also investigated. (10.1088/1361-6595/aa56d6)
DOI : 10.1088/1361-6595/aa56d6
In-situ preparation of ultra-small Pt nanoparticles within rod-shaped mesoporous silica particles: 3-D tomography and catalytic oxidation of n-hexane
- Uson Laura.
- Hueso Jose L..
- Sebastian Victor.
- Arenal Raul.
- Florea Ileana.
- Irusta Silvia.
- Arruebo Manuel.
- Santamaria Jesus.
Catalysis Communications, Elsevier, 2017, 100, pp.93--97. The shape and porous configuration of supports are key parameters to design outstanding catalysts. However, the selection of a proper mesoporous support, such as SBA-15, by itself does not guarantee accessibility to catalytic sites. The distribution of the active phase and its stability are strongly related to the procedure used to deposit it on the catalytic substrate. Herein, we have prepared rod-shaped SBA-15 silica supports functionalized with amine groups to facilitate the electrostatic attraction and a good distribution of the resulting Pt-based catalytic nanoparticles along the pore walls. Additionally, the use of tetrakis-(hydroxymethyl)-phosphonium chloride (THPC) as both reductant and stabilizer is presented as a novel alternative for Pt nanoparticle synthesis. The behaviour of this catalyst in the total oxidation of n-hexane demonstrates high activity and excellent stability after 70 h on reaction stream. STEM-HAADF and 3-D tomography were used to confirm the presence of the metallic nanoparticles within the mesochannels and to corroborate their reduced sintering after reaction. (10.1016/j.catcom.2017.06.022)
DOI : 10.1016/j.catcom.2017.06.022
Electric field and temperature in a target induced by a plasma jet imaged using Mueller polarimetry
- Slikboer Elmar
- Sobota Ana
- Guaitella Olivier
- Garcia-Caurel Enric
Journal of Physics D: Applied Physics, IOP Publishing, 2017, 51, pp.025204. Mueller polarimetry is used to investigate the behavior of an electro optic target (BSO crystal) under exposure of guided ionization waves produced by an atmospheric pressure plasma jet. For the first time, this optical technique is time resolved to obtain the complete Mueller matrix of the sample right before and after the impact of the discharges. By analyzing the induced birefringence, the spatial profiles and local values are obtained of both the electric field and temperature in the sample. Electric fields are generated due to deposited surface charges and a temperature profile is present, due to the heat transferred by the plasma jet. The study of electric field dynamics and local temperature increase at the target, due to the plasma jet is important for biomedical applications, as well as surface functionalization. This work shows how Mueller polarimetry can be used as a novel diagnostic to simultaneously acquire the spatial distribution and local values of both the electric field and temperature, by coupling the external source of anisotropy to the measured induced birefringence via the symmetry point group of the examined material. (10.1088/1361-6463/aa9b17)
DOI : 10.1088/1361-6463/aa9b17
Plasma nanotexturing of silicon surfaces for photovoltaics applications: influence of initial surface finish on the evolution of topographical and optical properties
- Fischer Guillaume
- Drahi Étienne
- Foldyna Martin
- Germer Thomas A.
- Johnson Erik V.
Optics Express, Optical Society of America - OSA Publishing, 2017, 25 (24). (10.1364/OE.25.0A1057)
DOI : 10.1364/OE.25.0A1057
Tuning the properties of F:SnO 2 (FTO) nanocomposites with S:TiO 2 nanoparticles – promising hazy transparent electrodes for photovoltaics applications
- Zhang Shan-Ting
- Foldyna Martin
- Roussel Hervé
- Consonni Vincent
- Pernot Etienne
- Schmidt-Mende Lukas
- Rapenne Laetitia
- Jimenez Carmen
- Deschanvres Jean-Luc
- Munoz-Rojas David
- Bellet Daniel
Journal of Materials Chemistry C, Royal Society of Chemistry, 2017, 5 (1), pp.91 - 102. (10.1039/C6TC04153A)
DOI : 10.1039/C6TC04153A
Influence of Hot-Carrier Extraction from a Photovoltaic Absorber: An Evaporative Approach
- Suchet Daniel
- Jehl Zacharie
- Okada Yoshitaka
- Guillemoles Jean-Francois
Physical Review Applied, American Physical Society, 2017, 8 (3), pp.034030. The effect of energy-selective extraction on a hot carrier’s population is addressed in this study. Using an evaporative cooling model inspired by the field of cold atoms, we derive an analytical expression supported by numerical calculations to account for the removal of particles from the distribution and subsequent energy redistribution among the remaining carriers. Depending on the filtering dimensionality and energy level of extraction, the distribution can be either heated up or cooled down, resulting in a modification of the current-voltage characteristic associated to the structure. The negative differential resistance peak indicating the selective extraction is shown to be markedly reduced when evaporation is considered, which may lead to an overestimation of the tunneling current in previous models. These results provide insights into the interpretation of experimental results on energy-selective contacts, as well as a straightforward method to unequivocally demonstrate the energy filtering of hot carriers in a structure operating under continuous illumination. (10.1103/physrevapplied.8.034030)
DOI : 10.1103/physrevapplied.8.034030

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