Publications associées à Recombination dynamics of single quantum dots in a fiber system at telecommunication wavelengths

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

Quench Detection and Temperature Measurement With Fiber Optic Sensors

Davide Uglietti, Kamil Sedlák, Christoph Müller

For the EU DEMO conductor testing, a temperature sensor based on Fiber Bragg Grating (FBG) optical fiber is studied at the EPFL Swiss Plasma Center. The SULTAN test facility has been upgraded to use fiber optic sensor for temperature monitoring and quench ...

IEEE Institute of Electrical and Electronics Engineers2024

High energy-density electrostatic actuators for soft robotics

Sylvain Thomas Schaller

This thesis reports high energy-density electrostatic actuators for use in soft robotics. This thesis has two main parts: a) a detailed study of electro-adhesion using microfabricated electrodes, and b) a flexi-ble fiber-shaped linear motor. Electro-adhesi ...

EPFL2024

Study of growth-induced point defects and their impact on InGaN-based optoelectronic devices

Yao Chen

GaN exhibits a decomposition tendency for temperatures far below its melting point and common growth temperatures used in metal-organic vapour phase epitaxy (MOVPE).This characteristic is known to be a major obstacle for realising GaN bulk substrate. There ...

EPFL2024

III-N blue-emitting epi-structures with high densities of dislocations: Fundamental mechanisms for efficiency improvement and applications

Pierre Christophe Lottigier

Since the dawn of humanity, human beings seeked to light their surroundings for their well-being, security and development. The efficiency of ancient lighting devices, e.g. oil lamps or candles, was in the order of 0.03-0.04% and jumped to 0.4-0.6% with th ...

EPFL2024

Advanced Silicon and SWIR Single-Photon Avalanche Diodes: Design, Simulation, and Characterization

Ekin Kizilkan

Low-level light detection with high spatial and timing accuracy is a growing area of interest by virtue of applications such as light detection and ranging (LiDAR), biomedical imaging, time-resolved Raman spectroscopy, and quantum applications. Single-phot ...

EPFL2024

Shortwave Infrared-Sensitive, Narrowband Organic Upconversion Devices with a Gain

Wei-Hsu Hu

Sensing and imaging of light in the shortwave infrared (SWIR) range is increasingly used in various fields, including bio-imaging, remote sensing, and semiconductor process control. SWIR-sensitive organic photodetectors (OPDs) are promising because organic ...

EPFL2024

Investigating Non-equilibrium Physics in Wide Bandgap Semiconductors and Quantum Materials via Ultrafast Spectroscopy

Hui-Yuan Chen

This thesis uses femtosecond laser spectroscopy in studying strong correlation in condensed matters that are pertinent to future technology: a wide bandgap perovskite and a quantum material, with the employment of ultrafast time-resolved spectroscopy in th ...

EPFL2024

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

Tunable pump compression and fast modulation for pulsed THz generation

Ileana-Cristina Benea-Chelmus, Shima Rajabali, Yazan Lampert Almahmoud, Alessandro Tomasino

We demonstrate tunable dispersion compensation of femtosecond pulses at telecom wavelengths for broadband Terahertz generation in 7.5-meter fiber link using a Silicon prism pair. The prism pair enhances the amplitude of the THz E-field in InGaAs photocondu ...

IEEE2023

Space-time wave packets with reduced divergence and tunable group velocity generated in free space after multi-mode fiber propagation

Tobias Kippenberg, Hao Song, Maxim Karpov, Xinzhou Su

Previously, space-time wave packets (STWPs) have been gen-erated in free space with reduced diffraction and a tunable group velocity by combining multiple frequency comb lines each carrying a single Bessel mode with a unique wave num-ber. It might be poten ...

Optica Publishing Group2023

Semiconductor-based device architectures in multimaterial fibers

William Nicolas Duncan Esposito

Semiconductor materials have given rise to today's digital technology and consumer electronics. Widespread adoption is closely linked to the ability to process and integrate them in devices at scale. Where flexibility and large surfaces are required, such ...

EPFL2023

Drift-Diffusion Simulations of Charge Transport and Trap Dynamics in Organic Semiconductor Materials

Camilla Arietta Vael-Garn

Polymeric semiconductors have gained significant attention in the field of organic electronics due to their unique properties and potential applications. Through their ability to transport charge carriers and to absorb or emit light, they have attracted mu ...

EPFL2023

Indoor Self-Powered Perovskite Optoelectronics with Ultraflexible Monochromatic Light Source

Felix Thomas Eickemeyer, Tommaso Marcato, Hiroaki Jinno, Lukas Pfeifer

Self-powered skin optoelectronics fabricated on ultrathin polymer films is emerging as one of the most promising components for the next-generation Internet of Things (IoT) technology. However, a longstanding challenge is the device underperformance owing ...

Wiley-V C H Verlag Gmbh2023

Towards semiconducting nano-engineered photocathodes for electron microscopy applications

Nicolas Tappy

The growing field of pulsed electron microscopy (PEM) currently suffers from technical challenges, many of which are related to the inefficiency of present pulsed emitters. In this research, we explore semiconductor photoemitters as a replacement of conven ...

EPFL2023

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

The mesoglea buffers the physico-chemical microenvironment of photosymbionts in the upside-down jellyfish Cassiopea sp

Anders Meibom, Niclas Heidelberg Lyndby, Michael Kühl

IntroductionThe jellyfish Cassiopea has a conspicuous lifestyle, positioning itself upside-down on sediments in shallow waters thereby exposing its photosynthetic endosymbionts (Symbiodiniaceae) to light. Several studies have shown how the photosymbionts b ...

FRONTIERS MEDIA SA2023

Process development of pre-impregnated hybrid thin-ply composites

Alexios Argyropoulos

Thin-ply composites, obtained with recently developed fiber spreading techniques, rapidly gained industrial interest because they offer a large composite design freedom, and lead to a composite tensile strength that is close to that of the individual fiber ...

EPFL2023

Sub-kHz-Linewidth External-Cavity Laser (ECL) With Si3N4 Resonator Used as a Tunable Pump for a Kerr Frequency Comb

Tobias Kippenberg, Junqiu Liu

Combining optical gain in direct-bandgap III-V materials with tunable optical feedback offered by advanced photonic integrated circuits is key to chip-scale external-cavity lasers (ECL), offering wideband tunability along with low optical linewidths. Exter ...

IEEE Institute of Electrical and Electronics Engineers2023

Soft Bending Actuator With Fiber-Jamming Variable Stiffness and Fiber-Optic Proprioception

Sudong Lee

Soft actuators with a function of variable stiffness are beneficial to the improvement of the adaptability of robots, expanding the application areas and environments. We propose a tendon-driven soft bending actuator that can change its stiffness using fib ...

Ieee-Inst Electrical Electronics Engineers Inc2023