Publications associées à Optimization of the efficiency of single photon sources based on quantum dots under optical excitation

Investigation of room-temperature single-photon emitters in GaN-based materials and GaN/AlN quantum dots

Over the past decade, quantum photonics platforms aiming at harnessing the fundamental properties of single particles, such as quantum superposition and quantum entanglement, have flourished. In this context, single-photon emitters capable of operating at ...

EPFL2024

Compact and effective photon-resolved image scanning microscope

Giorgio Tortarolo

Fluorescence confocal laser-scanning microscopy (LSM) is one of the most popular tools for life science research. This popularity is expected to grow thanks to single-photon array detectors tailored for LSM. These detectors offer unique single-photon spati ...

Spie-Soc Photo-Optical Instrumentation Engineers2024

Room-Temperature Quantum Optomechanics and Free-Electron Quantum Optics

Guanhao Huang

Quantum optics studies how photons interact with other forms of matter, the understanding of which was crucial for the development of quantum mechanics as a whole. Starting from the photoelectric effect, the quantum property of light has led to the develop ...

EPFL2024

Down-conversion of a single photon as a probe of many-body localization

Cristiano Ciuti

Decay of a particle into more particles is a ubiquitous phenomenon to interacting quantum systems, taking place in colliders, nuclear reactors or solids. In a nonlinear medium, even a single photon would decay by down-converting (splitting) into lower-freq ...

NATURE PORTFOLIO2023

Background Rejection in Two-Photon Fluorescence Image Scanning Microscopy

Giorgio Tortarolo

We discuss the properties of signal strength and integrated intensity in two-photon excitation confocal microscopy and image scanning microscopy. The resolution, optical sectioning and background rejection are all improved over nonconfocal two-photon micro ...

MDPI2023

Single molecule fluorescence and phosphorescence studies using a scanning tunneling microscope

Abhishek Grewal

This thesis investigates novel single-molecule luminescence phenomena at their inherent, sub-molecular length scale. The microscopic understanding of luminescence processes will be crucial for the continued improvement of organic optoelectronic and semicon ...

EPFL2022

Pixel super-resolution with spatially entangled photons

Edoardo Charbon, Jiuxuan Zhao

Pixelation is common in quantum imaging systems and limit the image spatial resolution. Here, the authors introduce a pixel super-resolution approach based on measuring the full spatially-resolved joint probability distribution of spatially-entangled photo ...

Nature Portfolio2022

Cavity-mediated electron-photon pairs

Rui Ning Wang, Tobias Kippenberg, Junqiu Liu, Arslan Sajid Raja, Guanhao Huang, Zheru Qiu, Yujia Yang

Quantum information, communication, and sensing rely on the generation and control of quantum correlations in complementary degrees of freedom. Free electrons coupled to photonics promise novel hybrid quantum technologies, although single-particle correlat ...

American Association for the Advancement of Science2022

n-photon blockade with an n-photon parametric drive

Fabrizio Minganti, Wei Qin

We propose a mechanism to engineer an n-photon blockade in a nonlinear cavity with an n-photon parametric drive lambda(adagger n + an). When an n-photon-excitation resonance condition is satisfied, the presence of n photons in the cavity suppress ...

AMER PHYSICAL SOC2021

Dark-level trapping, lateral confinement, and built-in electric field contributions to the carrier dynamics in c-plane GaN/AlN quantum dots emitting in the UV range

Nicolas Grandjean, Raphaël Butté, Sebastian Pascal Tamariz Kaufmann

c-plane GaN/AlN quantum dots (QDs) are promising zero-dimensional quantum nanostructures that exhibit single photon emission properties up to room temperature and even above. In this context, it is of prime interest to gain a deeper insight into the recomb ...

AMER INST PHYSICS2021

Functional Elements for Quantum-Dot-Based Integrated Quantum Photonics

Antoine Maxime Delgoffe

Quantum Integrated Photonics (QIP) harnesses quantum-states of light on tiny chips, from generation to processing and eventual detection. Within this context, this thesis explores functional QIP elements resulting from the monolithic integration of semicon ...

EPFL2020

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

Physics of optically driven nanojunctions

Philippe Andreas Rölli

Recent years have seen spectacular developments in the domain of nano-optics. Alongside the well-known techniques of super-resolution microscopy progress in nanofabrication has enabled important improvements in the fields of optical imaging and spectros ...

EPFL2020

Controlling free electrons with optical whispering-gallery modes

Tobias Kippenberg

Free-electron beams are versatile probes of microscopic structure and composition(1,2), and have revolutionized atomic-scale imaging in several fields, from solid-state physics to structural biology(3). Over the past decade, the manipulation and interactio ...

NATURE PUBLISHING GROUP2020

Molecular Platform for Frequency Upconversion at the Single-Photon Level

Christophe Marcel Georges Galland, Tobias Kippenberg, Philippe Andreas Rölli

Direct detection of single photons at wavelengths beyond 2 mu m under ambient conditions remains an outstanding technological challenge. One promising approach is frequency upconversion into the visible (VIS) or near-infrared (NIR) domain, where single-pho ...

American Physical Society2020

Room temperature single photon emission from planar GaN/AlN quantum dot samples grown by MBE

Nicolas Grandjean, Sebastian Pascal Tamariz Kaufmann, Gordon Jens Callsen

We present an overview on the growth and the optical properties of GaN quantum dots (QDs) embedded in planar AlN grown on the following three different types of substrates: single AlN crystal, AlN on sapphire, and AIN on Si(111). QD density control over th ...

IEEE2019

Quantum correlation measurement with single photon avalanche diode arrays

Claudio Bruschini, Edoardo Charbon, Ivan Michel Antolovic

Temporal photon correlation measurement, instrumental to probing the quantum properties of light, typically requires multiple single photon detectors. Progress in single photon avalanche diode (SPAD) array technology highlights their potential as high-perf ...

2019

Dynamics of nanoscale systems probed by time-resolved STM-induced luminescence

Anna Maria Roslawska

The efficiency and peculiarities of processes such as surface adsorption or electron-to-photon energy conversion in organic and inorganic structures are determined by the dynamics at the scale of individual molecules, atoms and charges. The timescales of s ...

EPFL2019

Scanning near-field optical microscopy with new probes and feedback modes

Anton Smirnov

Scanning Near-field Optical Microscopy (SNOM) technique enables to overcome Abbe diffraction limit of far-field optics as well as to obtain simultaneously optical and topographical images. While the optical resolution of the method is limited by the apertu ...

EPFL2019

Ultrafast carrier dynamics in III-nitride nanostructures and LED quantum efficiency

Wei Liu, Wei Liu

Since the seminal report about the first Candela- class-brightness InGaN blue light- emitting diodes (LEDs) by Shuji Nakamura et al. in 1994, III-nitride semiconductors have been one of the most important platforms for optoelectronic devices. The achieve ...

EPFL2019