Publications associées à Index ellipsoid

Wandering principal optical axes in van der Waals triclinic materials

Nature is abundant in material platforms with anisotropic permittivities arising from symmetry reduction that feature a variety of extraordinary optical effects. Principal optical axes are essential characteristics for these effects that define light-matte ...

Nature Portfolio2024

van der Waals Materials for Overcoming Fundamental Limitations in Photonic Integrated Circuitry

Arslan Mazitov

With the advance of on-chip nanophotonics, there is a high demand for high-refractive-index and low-loss materials. Currently, this technology is dominated by silicon, but van der Waals (vdW) materials with a high refractive index can offer a very advanced ...

AMER CHEMICAL SOC2023

Nonlinear Inverse Problems in Quantitative Phase Imaging

Thanh-An Michel Pham

The topic of this thesis is the development of new algorithmic reconstruction methods for quantitative phase imaging (QPI). In the past decade, advanced QPI has emerged as a valuable tool to study label-free biological samples and uncover their 3D structur ...

EPFL2022

Advanced Techniques in Optical Diffraction Tomography

Ahmed Bassam Sayed Ayoub Mohamed Emam

In this thesis, we study the 3 challenges described above. First, we study different reconstruction techniques and assess the fidelity of each reconstruction results by means of structured illumination and phase conjugation. By reconstructing the 3D refrac ...

EPFL2022

Particle suitable for the manufacture of an implantable soft tissue engineering material

Philippe Renaud, Thomas Michael Braschler, Amélie Barbara Hildegarde Béduer

The particle (1) is suitable for the manufacture of an implantable soft tissue engineering material and comprises: a three-dimensionally warped and branched sheet (2) where (i) the three-dimensionally warped and branched sheet (2) is made from a biocompati ...

2019

Rapid Performance Optimization Method for Photoelectrodes

Sophia Haussener, Yannick Kenneth Gaudy

We report the development of a rapid method for the performance optimization of photoelectrodes. The method requires as an input incident photon-to-current efficiency (IPCE) measurements of a material at two or more wavelengths, an estimation of the comple ...

2019

Local Structural Heterogeneity and Electromechanical Responses of Ferroelectrics: Learning from Relaxor Ferroelectrics

Dragan Damjanovic

Long-range ordering of dipoles is a key microscopic signature of ferroelectrics. These ordered dipoles form ferroelectric domains, which can be reoriented by electric fields. Relaxor ferroelectrics are a type of ferroelectric where the longrange ordering o ...

2018

Determination and optimization of material parameters of particle-based LaTiO2N photoelectrodes

Sophia Haussener, Ulrich Aschauer, Yannick Kenneth Gaudy

We developed a validated numerical model capable of predicting the photocurrent-voltage characteristics of oxide and oxynitride particle-based photoelectrodes and identifying the critical parameters affecting the performance of those photoelectrodes. We us ...

Royal Society of Chemistry2018

Complex Refractive Indices of Cesium–Formamidinium-Based Mixed-Halide Perovskites with Optical Band Gaps from 1.5 to 1.8 eV

Christophe Ballif, Jérémie Werner, Quentin Thomas Jeangros, Matthias Wolfgang Bräuninger, Gabriel Christmann, Florent Sahli, Arnaud Walter, Sylvain Nicolay, Björn Niesen, Gizem Nogay

Cesium-formamidinium-based mixed-halide perovskite materials with optical band gaps ranging from 1.5 to 1.8 eV are investigated by variable-angle spectroscopic ellipsometry. The determined complex refractive indices are shown to depend on the fabrication p ...

2018

High-Q surface modes in photonic crystal/iron garnet film heterostructures for sensor applications

Giovanni Dietler, Serguei Sekatski, Pavel Kapralov

A novel type of a plasmonic sensor based on a magnetophotonic plasmonic heterostructure with an ultrahigh-Q resonance is considered. A magnetoplasmonic resonance with an angular width of 0.06A degrees, which corresponds to a Q factor of 700 and is a record ...

Springer Verlag2017