Publications de Christian David

Hard X-ray helical dichroism of disordered molecular media

Majed Chergui, Jérôme Lacour, Christian David, Giulia Fulvia Mancini, Malte Oppermann, Dominik Kinschel, Oliviero Cannelli, Camila Bacellar Cases Da Silveira

Chirality is a structural property of molecules lacking mirror symmetry that has strong implications in diverse fields, ranging from life sciences to materials science. Chirality-sensitive spectroscopic methods, such as circular dichroism, exhibit weak sig ...

Nature Publishing Group2022

Three-dimensional imaging of integrated circuits with macro- to nanoscale zoom

Christian David, Michal Odstrcil, Gabriel Aeppli, Manuel Guizar Sicairos

The imaging of integrated circuits across different length scales is required for failure analysis, design validation and quality control. At present, such inspection is accomplished using a hierarchy of different probes, from optical microscopy on the mil ...

NATURE PUBLISHING GROUP2019

Seismic and Microseismic Signatures of Fluids in Rocks: Bridging the Scale Gap

Christian David, Lucas Xan Pimienta

The aim of this collection is to record a snapshot of our current state of understanding of the impact of fluids on the evolution and monitorability of subsurface rock formations during anthropogenic fluid injection/withdrawal operations, accounting for sc ...

AMER GEOPHYSICAL UNION2019

Towards X-ray transient grating spectroscopy

Majed Chergui, Paul Beaud, Christian David, Giulia Fulvia Mancini, Erwan Fabrice Koch, Jérémy Raymond Jean Maurice Rouxel

The extension of transient grating spectroscopy to the x-ray regime will create numerous opportunities, ranging from the study of thermal transport in the ballistic regime to charge, spin, and energy transfer processes with atomic spatial and femtosecond t ...

OPTICAL SOC AMER2019

Evolution in Seismic Properties During Low and Intermediate Water Saturation: Competing Mechanisms During Water Imbibition?

Christian David, Lucas Xan Pimienta

2019

Generation and measurement of sub-micrometer relativistic electron beams

Christian David, Rasmus Ischebeck, Eugenio Ferrari

The generation of low-emittance electron beams has received significant interest in recent years. Driven by the requirements of X-ray-free electron lasers, the emittance of photocathode injectors has been reduced significantly, with corresponding increase ...

2018

The ACHIP experimental chambers at the Paul Scherrer Institut

Leonid Rivkin, Christian David, Rasmus Ischebeck, Eugenio Ferrari, Sven Reiche

The Accelerator on a Chip International Program (ACHIP) is an international collaboration, funded by the Gordon and Betty Moore Foundation, with the goal of demonstrating that laser-driven accelerator can be integrated on a chip to fully build an accelerat ...

ELSEVIER SCIENCE BV2018

Pressure-dependent elastic and transport properties of porous and permeable rocks: Microstructural control

Christian David, Lucas Xan Pimienta

Although several studies aimed at linking electrical and hydraulic transport properties in rocks, the existing models remain at most incomplete. Based on this observation, in addition to the transport properties, this contribution investigates the pressure ...

Amer Geophysical Union2017

Investigation of the dominant 1/f noise source in silicon nanowire sensors

Jan Brunner, Sara Rigante, Christian David

We analyzed 1/f noise in silicon nanowire ion-sensitive field-effect transistors (SiNW-ISFETs) having different wire widths ranging from 100 nm to 1 pin and operated under different gating conditions in order to determine the noise source and the sensor ac ...

Elsevier2014

Multiple Scattering Tomography

Christian David, Peter Modregger, Marco Stampanoni

Multiple scattering represents a challenge for numerous modern tomographic imaging techniques. In this Letter, we derive an appropriate line integral that allows for the tomographic reconstruction of angular resolved scattering distributions, even in the p ...

Amer Physical Soc2014

Two-dimensional ultra-small angle X-ray scattering with grating interferometry

Simon Rutishauser, Christian David, Peter Modregger, Marco Stampanoni

It was recently established that the pixel-wise ultra-small angle x-ray distribution can be retrieved with grating interferometry. However, in these one dimensional approaches the contrast was limited to the direction orthogonal to the structure of the lin ...

AIP American Institute of Physics2014

A sensitive x-ray phase contrast technique for rapid imaging using a single phase grid analyzer

Simon Rutishauser, Christian David, Peter Modregger, Marco Stampanoni

Phase contrast x-ray imaging (PCXI) is a promising imaging modality, capable of sensitively differentiating soft tissue structures at high spatial resolution. However, high sensitivity often comes at the cost of a long exposure time or multiple exposures p ...

Optical Society of America2013

pH Response of Silicon Nanowire Sensors: Impact of Nanowire Width and Gate Oxide

Sara Rigante, Christian David

We present a systematic study of the performance of silicon nanowires (SiNWs) with different widths when they are used as ion-sensitive field-effect transistors (ISFETs) in pH-sensing experiments. The SiNW widths ranged from 100 nm to 1 mu m. The SiNW-ISFE ...

Myu, Scientific Publishing Division2013

The Challenge of Connecting the Dots in the BRAIN

Pierre Magistretti, Christian David

The Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative has focused scientific attention on the necessary tools to understand the human brain and mind. Here, we outline our collective vision for what we can achieve within a dec ...

Elsevier2013

A tilted grating interferometer for full vector field differential x-ray phase contrast tomography

Simon Rutishauser, Christian David, Peter Modregger, Marco Stampanoni

We report on a setup for differential x-ray phase-contrast imaging and tomography, that measures the full 2D phase-gradient information. The setup uses a simple one-dimensional x-ray grating interferometer, in which the grating structures of the interferom ...

Optical Society of America2012

Imaging the Ultrasmall-Angle X-Ray Scattering Distribution with Grating Interferometry

Christian David, Peter Modregger, Marco Stampanoni

American Physical Society2012

Sensitivity of X-ray grating interferometry

Simon Rutishauser, Christian David, Peter Modregger, Marco Stampanoni

It is known that the sensitivity of X-ray phase-contrast grating interferometry with regard to electron density variations present in the sample is related to the minimum detectable refraction angle. In this article a numerical framework is developed that ...

Optical Society of America2011

High resolution, large field of view x-ray differential phase contrast imaging on a compact setup

Christian David, Peter Modregger, Marco Stampanoni

X-ray grating interferometry is a well established technique to perform differential phase contrast imaging on conventional x-ray tubes. So far, the application of this technique in commercial micro computed tomography scanners has remained a major challen ...

American Institute of Physics2011

Coherence and wavefront characterization of Si-111 monochromators using double-grating interferometry

Christian David

A study of the coherence and wavefront properties of a pseudo-channel-cut monochromator in comparison with a double-crystal monochromator is presented. Using a double-grating interferometer designed for the hard X-ray regime, the complex coherence factor w ...

2010

Advanced phase-contrast imaging using a grating interferometer

Christian David, Marco Stampanoni

Phase-sensitive X-ray imaging methods can provide substantially increased contrast over conventional absorption-based imaging, and therefore new and otherwise inaccessible information. Differential phase-contrast (DPC) imaging, which uses a grating interfe ...

2009