Publications associées à Position controlled self-catalyzed growth of GaAs nanowires by molecular beam epitaxy

Growth and Doping Mechanisms of III-V Nanostructures by Selective Area Epitaxy

Selective area epitaxy (SAE), applied to semiconductor growth, allows tailored fabrication of intricate structures at the nanoscale with enhanced properties and functionalities. In the field of nanowires (NWs), it adds scalability by enabling the fabricati ...

EPFL2024

Plasmonic Nanostructures for Photocatalysis: Material, Photonic and Electronic Effects

Fateme Kiani Shahvandi

Plasmonic photochemistry has a large potential to replace energy-intensive chemical processes with low-temperature, low-pressure light-driven chemical reactions. Plasmonic nanostructures have emerged as promising photocatalysts with exceptional and tunable ...

EPFL2024

Accretion Disk Size and Updated Time-delay Measurements in the Gravitationally Lensed Quasar SDSS J165043.44+425149.3

Frédéric Courbin, Martin Raoul Robert Millon

We analyze variability in 15-season optical lightcurves from the doubly imaged lensed quasar SDSS J165043.44+425149.3 (SDSS1650), comprising five seasons of monitoring data from the Maidanak Observatory (277 nights in total, including the two seasons of da ...

Iop Publishing Ltd2024

Resolving the vicinity of supermassive black holes with gravitational microlensing

Georgios Vernardos

Upcoming wide-field surveys will discover thousands of new strongly lensed quasars which will be monitored with unprecedented cadence by the Legacy Survey of Space and Time (LSST). Many of these quasars will undergo caustic-crossing events over the 10-yr L ...

Oxford Univ Press2024

Instability and trajectories of buoyancy-driven annular disks: A numerical study

François Gallaire, Pier Giuseppe Ledda, Giovanni Vagnoli

We investigate the stability of the steady vertical path and the emerging trajectories of a buoyancy -driven annular disk as the diameter of its central hole is varied. The steady and axisymmetric wake associated with the steady vertical path of the disk, ...

Amer Physical Soc2024

Long live(d) CsPbBr3 superlattices: colloidal atomic layer deposition for structural stability

Raffaella Buonsanti, Alexander Nicolas Chen, Philippe Benjamin Green, Victoria Lapointe

Superlattice formation afforded by metal halide perovskite nanocrystals has been a phenomenon of interest due to the high structural order induced in these self-assemblies, an order that is influenced by the surface chemistry and particle morphology of the ...

Royal Soc Chemistry2024

Scalable Approaches to III-V Nanowires for Photodetection

Nicholas Paul Morgan

III-V semiconductor nanowires have unique properties that make them ideal for advanced photodetectors on inexpensive substrates. For example, they exhibit enhanced or polarization-dependent light absorption, they can form complex heterostructures, and thei ...

EPFL2023

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

From Layer-by-Layer Growth to Nanoridge Formation: Selective Area Epitaxy of GaAs by MOVPE

Alok Rudra, Anna Fontcuberta i Morral, Nicholas Paul Morgan, Marie Sophie Sanglé-Ferrière, Didem Dede, Valerio Piazza, Ann-Kristin Stief, Vladimir Dubrovskii

We outline the growth mechanismand shape evolution of GaAsnanoridges by selective area MOVPE with three well-identified, distinctstages of growth. ...

AMER CHEMICAL SOC2023

Strong gravitational lensing by AGNs as a probe of the quasar-host relations in the distant Universe

Malte Tewes, Frédéric Courbin, Martin Raoul Robert Millon, Aymeric Alexandre Galan

A rare case of a quasar acting as a gravitational lens allows a precise determination of the mass of the quasar's host galaxy and offers a new path to studying the connections between supermassive black holes and their host galaxies. ...

NATURE PORTFOLIO2023

GeSn as next-generation material for short-wave infrared single-photon detection

Andrea Giunto

In recent years, the automotive industry has aspired to bring self-driving vehicles to the general public and light detection and ranging (LiDAR) sensors have emerged as the preferred solution for car vision systems. At present, LiDAR technologies employ e ...

EPFL2023

Surfactant behavior and limited incorporation of indium during in situ doping of GeSn grown by molecular beam epitaxy

Anna Fontcuberta i Morral, Andrea Giunto, Thomas Hagger, Louise Emma Webb

GeSn is a promising group-IV semiconductor material for on-chip Si photonics devices and high-mobility transistors. These devices require the use of doped GeSn regions, achieved preferably in situ during epitaxy. From the electronic valence point of view, ...

AMER PHYSICAL SOC2023

Primordial black hole isocurvature modes from non-Gaussianity

Primordial black holes (PBHs) are black holes that might have formed in high density regions in the early universe. The presence of local-type non-Gaussianity can lead to large-scale fluctuations in the PBH formation rate. If PBHs make up a non-negligible ...

IOP Publishing Ltd2023

Coherent Hole Transport in Selective Area Grown Ge Nanowire Networks

Alok Rudra, Anna Fontcuberta i Morral, Nicholas Paul Morgan, Andrea Giunto, Santhanu Panikar Ramanandan

Holes in germanium nanowires have emerged as a realistic platform for quantum computing based on spin qubit logic. On top of the large spin–orbit coupling that allows fast qubit operation, nanowire geometry and orientation can be tuned to cancel out charge ...

American Chemical Society (ACS)2022

GaN growth on ScAlMgO4 substrates via thermally-dewetted thin Al films

Elison de Nazareth Matioli, Alessandro Floriduz

In this note, we demonstrate the high-temperature growth of GaN on ScAlMgO4 substrates by metalorganic vapor phase epitaxy when a thin Al film is deposited ex situ on the ScAlMgO4 surface, prior to GaN growth. Mirror-like high-quality GaN epitaxial layers ...

IOP Publishing Ltd2022

Controlled filamentation instability as a scalable fabrication approach to flexible metamaterials

Fabien Sorin, Louis Marie Philippe Martin-Monier, Pierre-Luc Eloi Piveteau, William Nicolas Duncan Esposito

Long and flexible arrays of nanowires find impactful applications in sensing, photonics, and energy harvesting. Conventional manufacturing relies largely on lithographic methods limited in wafer size, rigidity, and machine write time. Here, we report a sca ...

Nature Portfolio2022

Nanoscale Growth Initiation as a Pathway to Improve the Earth-Abundant Absorber Zinc Phosphide

Anna Fontcuberta i Morral, Elias Zsolt Stutz, Jean-Baptiste Leran, Mahdi Zamani, Simon Robert Escobar Steinvall, Rajrupa Paul, Mirjana Dimitrievska

Growth approaches that limit the interface area between layers to nanoscale regions are emerging as a promising pathway to limit the interface defect formation due to mismatching lattice parameters or thermal expansion coefficient. Interfacial defect mitig ...

AMER CHEMICAL SOC2022

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

Wafer-scale MoS2 with water-vapor assisted showerhead MOCVD

Andras Kis, Aleksandra Radenovic, Yanfei Zhao, Michal Daniel Macha, Mukeshchand Thakur, Jing Zhang, Mukesh Kumar Tripathi, Hyungoo Ji

Among numerous thin film synthesis methods, metalorganic chemical vapor deposition performed in a showerhead reactor is the most promising one for broad use in scalable and commercially adaptable two-dimensional material synthesis processes. Adapting the m ...

ROYAL SOC CHEMISTRY2022

Selective area epitaxy of GaAs: the unintuitive role of feature size and pitch

Anna Fontcuberta i Morral, Lucas Güniat, Martin George Friedl, Nicholas Paul Morgan, Akshay Balgarkashi, Didem Dede, Elif Nur Dayi, Valerio Piazza, Vladimir Dubrovskii

Selective area epitaxy (SAE) provides the path for scalable fabrication of semiconductor nanostructures in a device-compatible configuration. In the current paradigm, SAE is understood as localized epitaxy, and is modelled by combining planar and self-asse ...

IOP Publishing Ltd2022