Publications associées à Molecular dynamics simulations of shock compressed heterogeneous materials. II. The graphite/diamond transition case for astrophysics applications

Pressure-freezing of dodecane: exploring the crystal structures, formation kinetics and phase diagrams for colossal barocaloric effects in n-alkanes

Barocaloric (BC) materials provide cheaper and more energy efficient alternatives to traditional refrigerants. Some liquid alkanes were recently shown to exhibit a colossal BC effect, matching the entropy changes in commercial vapour-liquid refrigerants. D ...

Royal Soc Chemistry2023

High-precision optical magnetometry using Nitrogen Vacancies in CVD diamond

Hossein Babashah

Sensing weak magnetic fields is a topic of great importance in basic science and technology due to its wide range of applications. In this context, solid-state and nanoscale quantum sensors are poised to revolutionize the sensing platforms due to their ult ...

EPFL2023

Hot rocks: Constraining the thermal conditions of the Mistastin Lake impact melt deposits using zircon grain microstructures

Cyril Cayron

The production of superheated melt during hypervelocity impact events has been proposed to be a common occurrence on terrestrial planetary bodies. Recent direct evidence of superheated impact melt temperatures exceeding > 2370 degrees C from the Kamestasti ...

ELSEVIER2022

On the structure of (111) twist grain boundaries in diamond: atomistic simulations with Tersoff-type interatomic potentials

Carolina Baruffi

In nanocrystalline diamond thin films, the high grain boundary density and the associated grain boundary properties may dominate the overall material behavior. In the present work, we systematically investigate (111) twist grain boundaries in diamond carbo ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Quantum vibronic effects on the electronic properties of solid and molecular carbon

François Gygi, Michele Ceriotti, Han Yang

We study the effect of quantum vibronic coupling on the electronic properties of carbon allotropes, including molecules and solids, by combining path integral first principles molecular dynamics (FPMD) with a colored noise thermostat. In addition to avoidi ...

AMER PHYSICAL SOC2021

Exploring optically active defects in wide-bandgap materials using fluorescence microscopy

Evgenii Glushkov

Defects in solid-state systems can be both detrimental, deteriorating the quality of materials, or desired, thanks to the novel functionality they bring. Optically active point defects, producing fluorescent light, are a great example of the latter. Natura ...

EPFL2021

Diamond on GaN integration for power semiconductor devices with efficient thermal management

Reza Soleiman Zadeh Ardebili

The international actions against global warming demands reductions in carbon emission and more efficient use of energy. Energy efficiency in the conversion and use of electricity, as an important form of energy in the modern life, has strong environmental ...

EPFL2021

Leaking Secrets Through Compressed Caches

Daniel Felipe Forero Sanchez

We offer the first security analysis of cache compression, a promising architectural technique that is likely to appear in future mainstream processors. We find that cache compression has novel security implications because the compressibility of a cache l ...

IEEE COMPUTER SOC2021

Nanosecond pulsed laser-processing of CVD diamond

Patrik Willi Hoffmann, Marco Cantoni, Sébastien Equis

This work considers the resulting material structural effects of laser-processing chemical vapor deposited (CVD) diamond. The utilized 532 nm wavelength laser had a pulse duration of 40 ns together with a spot diameter of ca. 40 mu m. The effect of cutting ...

ELSEVIER SCI LTD2020

Combined synchrotron x-ray diffraction and NV diamond magnetic microscopy measurements at high pressure

Charles Michel Henri Pépin, Margarita Lesik Gaussens, Mayeul Sylvain Chipaux

We report the possibility to simultaneously perform wide-field nitrogen-vacancy (NV) diamond magnetic microscopy and synchrotron x-ray diffraction measurements at high pressure. NV color centers are created on the culet of a diamond anvil which is integrat ...

2020

Diffraction artefacts from twins and stacking faults, and the mirage of hexagonal, polytypes or other superstructures

Cyril Cayron

Recently, a hexagonal phase has been reported in high carbon steels in several studies. Here, we show that the electron microscopy results used in these studies were erroneously interpreted. The extra-spots in the diffraction patterns and the odd contrasts ...

2020

Advanced Diamond Microfabrication for Microoptics and Photonics

Marcell Kristof Kiss

Diamond is an exceptional material - hard, stiff, transparent, which makes it ideal for the fabrication of optical and mechanical systems that take advantage of these properties. Diamond is not only "better", but it offers the possibility of integrating br ...

EPFL2019

Sequential catalysis enables enhanced C-C coupling towards multi-carbon alkenes and alcohols in carbon dioxide reduction: a study on bifunctional Cu/Au electrocatalysts

Michael Graetzel, Shaik Mohammed Zakeeruddin, Dan Ren, Jing Gao

Electrochemical reduction of carbon dioxide (CO2) to multi-carbon products such as ethylene, ethanol and n-propanol offers a promising path for utilization of excessive CO2 and energy storage. Oxide-derived Cu electrodes are among the best electrocatalysts ...

ROYAL SOC CHEMISTRY2019

Fabrication and Characterization of Freestanding Single Crystal Diamond and Silicon Microresonators

Teodoro Graziosi

Microresonators are fundamental building blocks of any photonic integrated circuit, as they can be used as filters, modulators, sensors, and to enhance light emission. If these resonators are suspended and are free to oscillate, we can exploit the interact ...

EPFL2019

Reply to Comment by Jennings et al. on "Investigating Earth's Formation History Through Copper and Sulfur Metal-Silicate Partitioning During Core-Mantle Differentiation"

James Badro

Recognizing existing materials that can act as proxies for Earth's building blocks, and understanding the accretionary pathway taken during Earth's growth, persist as outstanding issues in need of resolution. In Mahan, Siebert, Blanchard, Badro, et al. (20 ...

AMER GEOPHYSICAL UNION2019

Shock-produced high-pressure (La, Ce, Th)PO4 polymorph revealed by microstructural phase heritage of monazite

Cyril Cayron

The responses of uranium-bearing accessory minerals to shock metamorphism have received growing interest, because under extreme pressure and temperature conditions, these phases can form unique microstructures and/or polymorphs and their radiometric ages c ...

GEOLOGICAL SOC AMER, INC2019

Near-Optimal Noisy Group Testing via Separate Decoding of Items

Volkan Cevher, Jonathan Mark Scarlett

In this paper, we revisit an efficient algorithm for noisy group testing in which each item is decoded separately (Malyutov and Mateev, 1980), and develop novel performance guarantees via an information-theoretic framework for general noise models. For the ...

IEEE2018

The small RNA RyhB is a regulator of cytochrome expression in Shewanella oneidensis

Rizlan Bernier-Latmani, Karin Lederballe Meibom

Shewanella oneidensis produces an extensive electron transfer network that results in metabolic flexibility. A large number of c-type cytochromes are expressed by S. oneidensis and these function as the fundamental electron transport chain proteins. Althou ...

Frontiers Media SA2018

From 2D to 3D Characterization of Materials Subjected to Extreme Pressure and Temperature Conditions

Farhang Nabiei

Planetesimal were the first planetary objects to form in the solar system, which later grew to make the proto-planets. Most of these bodies were differentiated as a result of internal heating. Several differentiated bodies have, then, been accreted followi ...

EPFL2017

Cubic zirconia in >2370◦C impact melt records Earth’s hottest crust

Cyril Cayron

Bolide impacts influence primordial evolution of planetary bodies because they can cause instantaneous melting and vaporization of both crust and impactors. Temperatures reached by impact-generated silicate melts are unknown because meteorite impacts are e ...

Elsevier2017