Publications associées à Monte Carlo model for the photoluminescence kinetics of a quantum dot embedded in a nanocavity

Hausdorff dimension of fermions on a random lattice

Geometric properties of lattice quantum gravity in two dimensions are studied numerically via Monte Carlo on Euclidean Dynamical Triangulations. A new computational method is proposed to simulate gravity coupled with fermions, which allows the study of int ...

Elsevier2024

Synthesis and properties of heterostructures in nanowires and 2-D materials

Akshay Balgarkashi

Modern solid-state devices were made possible by the discovery of semiconductor heterostructures. Heterostructures offer the ability to fabricate low-dimensional nanostructures such as quantum dots which can restrain carriers in all three-directions. Quant ...

EPFL2022

Toward Bright and Pure Single Photon Emitters at 300 K Based on GaN Quantum Dots on Silicon

Nicolas Grandjean, Raphaël Butté, Sebastian Pascal Tamariz Kaufmann, Johann Nicolaï Stachurski, Kanako Shojiki, Gordon Jens Callsen

Quantum dots (QDs) based on III-nitride semi-conductors are promising for single photon emission at noncryogenic temperatures due to their large exciton binding energies. Here, we demonstrate GaN QD single photon emitters operating at 300 K with g((2)) (0) ...

AMER CHEMICAL SOC2020

Direct Observation of Shallow Trap States in Thermal Equilibrium with Band‐Edge Excitons in Strongly Confined CsPbBr 3 Perovskite Nanoplatelets

Jacques-Edouard Moser, Etienne Christophe Socie, Andrés Burgos Caminal, Brener Rodrigo De Carvalho Vale

Lead halide perovskites exhibit great potential for light-emitting devices. Enhanced photoluminescence (PL) is obtained in perovskite materials of reduced dimensionalities due to the large exciton binding energy. However, as the nanocrystal size is reduced ...

2021

Mechanisms shifting the emission energy of self-assembled quantum dots in nanowires

Luca Francaviglia

This thesis is dedicated to the engineering of the emission energy of quantum dots embedded in core-shell GaAs-AlGaAs nanowires. The goal is to redshift the quantum-dot emission energy in resonance with a gas of Rb atoms. Segregation processes on the nanow ...

EPFL2019

Photocatalytic ammonia production enhanced by a plasmonic near-field and hot electrons originating from aluminium nanostructures

Christian Santschi, Olivier Martin, Madasamy Thangamuthu

Ammonia production at room temperature and atmospheric pressure is in high demand to assist in energy saving and the protection of the environment worldwide, as well as to help reduce CO2 emissions. Recently, plasmonic nanomaterials have been frequently us ...

2019

Transport of hot carriers in plasmonic nanostructures

Giulia Tagliabue

Plasmonic hot carrier devices extract excited carriers from metal nanostructures before equilibration and have the potential to surpass semiconductor light absorbers. However their efficiencies have so far remained well below theoretical limits, which nece ...

AMER PHYSICAL SOC2019

Exciton Dynamics and Effects of Structural Order in Morphology-Controlled J-Aggregate Assemblies

Frank Nüesch, Surendra Babu Anantharaman, Jakob Heier

Narrow-band photoluminescence (PL) together with high quantum efficiency from organic molecules is essential for high-color-purity emitters. Supramolecular assemblies like J-aggregates are promising materials due to their narrow PL signal with full-width a ...

2019

Femtosecond Spectroscopy of Au Hot-Electron Injection into TiO2: Evidence for Au/TiO(2 )Plasmon Photocatalysis by Bactericidal Au Ions and Related Phenomena

Juan Kiwi, Sami Rtimi

In the present work, we provide evidence for visible light irradiation of the Au/TiO2 nanoparticles' surface plasmon resonance band (SPR) leading to electron injection from the Au nanoparticles to the conduction band of TiO2. The Au/TiO2 SPR band is shown ...

2019

Single Photon Counting UV Solar-Blind Detectors Using Silicon and III-Nitride Materials

Edoardo Charbon, Preethi Padmanabhan

Ultraviolet (UV) studies in astronomy, cosmology, planetary studies, biological and medical applications often require precision detection of faint objects and in many cases require photon-counting detection. We present an overview of two approaches for ac ...

2016

Direct Comparison of Second Harmonic Generation and Two-Photon Photoluminescence from Single Connected Gold Nanodimers

Olivier Martin, Jérémy Butet

In this article we compare the two-photon photoluminescence and second harmonic generation from single connected gold nanodimers. Analyzing the particle size-dependent nonlinear optical spectra and performing excitation polarization resolved measurements u ...

American Chemical Society2016

Analyzing blinking effects in super resolution localization microscopy with single-photon SPAD imagers

Claudio Bruschini, Edoardo Charbon, Samuel Burri, Ivan Michel Antolovic

For many scientific applications, electron multiplying charge coupled devices (EMCCDs) have been the sensor of choice because of their high quantum efficiency and built-in electron amplification. Lately, many researchers introduced scientific complementary ...

Spie-Int Soc Optical Engineering2016

Probing the dynamics of plasmon-excited hexanethiol-capped gold nanoparticles by picosecond X-ray absorption spectroscopy

Majed Chergui, Thomas James Penfold, Jochen Rittmann

Picosecond X-ray absorption spectroscopy (XAS) is used to investigate the electronic and structural dynamics initiated by plasmon excitation of 1.8 nm diameter Au nanoparticles (NPs) functionalised with 1-hexanethiol. We show that 100 ps after photoexcitat ...

Royal Society of Chemistry2014

Dilute-Nitride Low-Dimensional Nanostructures Formed on Non-Planar Substrates

Romain Carron

The properties of semiconductors heterostructures of nanoscopic dimensions change from that of bulk material according to the rules of quantum mechanics. The planar quantum wells (QWs) are widely used in various diode and laser devices thanks to the relati ...

EPFL2013

High-performance pure blue phosphorescent OLED using a novel bis-heteroleptic iridium(III) complex with fluorinated bipyridyl ligands

Michael Graetzel, Mohammad Khaja Nazeeruddin

A novel pure blue phosphorescent emitter FK306 with fluorinated bipyridyl ligands was developed. The I-p level was determined to be 6.3 eV by photoelectron yield spectroscopy (PYS) in the solid state. The photophysical properties of a FK306/mCP film were e ...

Royal Society of Chemistry2013

Stencil-Nanopatterned Back Reflectors for Thin-Film Amorphous Silicon n-i-p Solar Cells

Christophe Ballif, Céline Pahud, Jürgen Brugger, Oscar Vazquez Mena, Andreea Veronica Savu, Mona Julia Katharina Klein, Franz-Josef Haug

We fabricated amorphous silicon n-i-p solar cells with two types of nanopatterned back reflectors using stencil lithography. One reflector type has a plasmonic grating that is embedded in the ZnO layer; the other one has a metallic grating patterned on top ...

Ieee-Inst Electrical Electronics Engineers Inc2013

Enhanced spontaneous emission from quantum dots in short photonic crystal waveguides

Laurent Balet

We report a study of the quantum dot (QD) emission in short photonic crystal waveguides. We observe that the quantum dot photoluminescence intensity and decay rate are strongly enhanced when the emission energy is in resonance with Fabry-Perot (FP) cavity ...

AIP American Institute of Physics2012

Stencil-nanopatterned back reflectors for thin-film amorphous silicon n-i-p solar cells

Christophe Ballif, Céline Pahud, Jürgen Brugger, Oscar Vazquez Mena, Andreea Veronica Savu, Mona Julia Katharina Klein, Franz-Josef Haug

We fabricated amorphous silicon n-i-p solar cells with two types of nanopatterned back reflectors using stencil lithography. One reflector type has a plasmonic grating that is embedded in the ZnO layer; the other one has a metallic grating patterned on top ...

Ieee2012

Electronic and Optical Properties of Semiconductor Quantum Dots

Guillaume Jean Tarel

This thesis is devoted to theoretically study the systems of single quantum dots (QDs) embedded in various photonic nanostructures, in close relation with experimental data. The word single is essential: due to their nanometer size, QDs have mainly been st ...

EPFL2011

Scanning Tunneling Microscopy and Luminescence of Individual Nanostructures

Theresa Lutz

A detailed investigation and characterization of the local properties of individual nanoscopic structures is of great importance for the understanding of novel physical phenomena at the nanoscale as well as for the assessment of their possible use in futur ...

EPFL2011