Publications de Nicolas Tappy | EPFL Graph Search

Towards semiconducting nano-engineered photocathodes for electron microscopy applications

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

Light emission properties of mechanical exfoliation induced extended defects in hexagonal boron nitride flakes

Anna Fontcuberta i Morral, Nicolas Tappy

Recently, hexagonal boron nitride (hBN) has become an interesting platform for quantum optics due to its peculiar defect-related luminescence properties. Concomitantly, hBN was established as the ideal insulating support for realizing 2D materials devices, ...

IOP Publishing Ltd2022

Boron quantification, concentration mapping and picosecond excitons dynamics in High-Pressure-High-Temperature diamond by cathodoluminescence

Anna Fontcuberta i Morral, Nicolas Tappy

Diamond is one of the most promising materials for high power and extreme conditions electronics. For this to become a reality, incorporation of active dopants needs to be understood. In this article we demonstrate how cathodoluminescence spectroscopy can ...

2022

Nanoscale Mapping of Light Emission in Nanospade-Based InGaAs Quantum Wells Integrated on Si(100): Implications for Dual Light-Emitting Devices

Anna Fontcuberta i Morral, Didem Dede, Valerio Piazza, Jean-Baptiste Leran, Raphaël François Lemerle, Wonjong Kim, Nicolas Tappy, Nicholas Paul Morgan, Akshay Balgarkashi, Titouan Charvin

III-V semiconductors outperform Si in many optoelectronics applications due to their high carrier mobility, efficient light emission and absorption processes, and the possibility to engineer their band gap through alloying. However, complementing Si techno ...

2022

Deconvolution of Light-Induced Ion Migration Phenomena by Statistical Analysis of Cathodoluminescence in Lead Halide-Based Perovskites

Mohammad Khaja Nazeeruddin, Paul Joseph Dyson, Ulf Anders Hagfeldt, Nicolas Tappy, Erfan Shirzadi

Studying the compositional instability of mixed ion perovskites under light illumination is important to understand the mechanisms underlying their efficiency and stability. However, current techniques are limited in resolution and are unable to deconvolut ...

WILEY2022

Boron-Doped-HPHT-Diamond CL Dataset

Nicolas Tappy

Cathodoluminescence datasets and analysis notebooks accompanying the following publication: https://doi.org/10.1016/j.carbon.2022.01.030 The analysis files rely on the development hyperspy version at the time of release (1.6.1). If compatibility issues a ...

Zenodo2022

Image shift correction, noise analysis, and model fitting of (cathodo-)luminescence hyperspectral maps

Anna Fontcuberta i Morral, Nicolas Tappy

Hyperspectral imaging is an important asset of modern spectroscopy. It allows us to perform optical metrology at a high spatial resolution, for example in cathodoluminescence in scanning electron microscopy. However, hyperspectral datasets present added ch ...

2022

Porous Nitride Light-Emitting Diodes

Anna Fontcuberta i Morral, Nicolas Tappy, Nuno Amador Mendez

A porous InGaN/GaN blue light-emitting diode is demonstrated using selective area sublimation. Transmission electron microscopy reveals that the structure is porous down to the Si substrate; however, the porosity is higher in the GaN buffer, while smaller ...

2022

Accompanying dataset to ACS Appl. Nano Mater. 2022, 5, 4, 5508–5515 : Nanoscale Mapping of Light Emission in Nanospade-Based InGaAs Quantum Wells Integrated on Si(100): Implications for Dual Light-Emitting Devices

Anna Fontcuberta i Morral, Didem Dede, Valerio Piazza, Raphaël François Lemerle, Jean-Baptiste Leran, Wonjong Kim, Nicolas Tappy, Nicholas Paul Morgan, Akshay Balgarkashi

Accompanying dataset containing the raw data and analysis contained in the main publication. This comprises the fitted CL-SEM dataset, the CL-STEM dataset, the CL-SEM presented in the SI and the STEM-EDX linescans. ...

Zenodo2022

Dataset for "Cubic, hexagonal and tetragonal FeGex phases (x = 1, 1.5, 2): Raman spectroscopy and magnetic properties"

Anna Fontcuberta i Morral, Dirk Grundler, Santhanu Panikar Ramanandan, Nicolas Tappy, Mirjana Dimitrievska, Anna Kúkol'ová

Raw data associated to the manuscript “Cubic, hexagonal and tetragonal FeGex phases (x = 1, 1.5, 2): Raman spectroscopy and magnetic properties", CrystEngComm 2021, XXXX, XXX, XXX-XXX There is currently an emerging drive to computational materials design ...

Zenodo2021