Publications associées à Ultrafast spectroscopy of wide bandgap semiconductor nanostructures

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

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

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

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

Johann Nicolaï Stachurski

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

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

Persistent enhancement of exciton diffusivity in CsPbBr3 nanocrystal solids

Seryio Saris

In semiconductors, exciton or charge carrier diffusivity is typically described as an inherent material property. Here, we show that the transport of excitons among CsPbBr3 perovskite nanocrystals (NCs) depends markedly on how recently those NCs were occup ...

Amer Assoc Advancement Science2024

Exciton migration in two-dimensional materials

Excitons play an essential role in the optical response of two-dimensional materials. These are bound states showing up in the band gaps of many-body systems and are conceived as quasiparticles formed by an electron and a hole. By performing real-time simu ...

Nature Portfolio2024

Microstructural and electrical characterization of high temperature passivating contacts for silicon solar cells

Sofia Libraro

Recombination at metal/semiconductor interfaces represents the main limitation in mainstream c-Si solar cells, primarily based on the passivated emitter and rear cell (PERC) concept. Full-area passivating contacts based on SiOx/poly-Si stacks are a candida ...

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

Dataset to accompany publication "Best practices in measuring absorption at the macro- and microscale"

Giulia Tagliabue, Fateme Kiani Shahvandi, Jiaming Ma, Alan Richard Bowman

This dataset accompanies the publication "Best practices in measuring absorption at the macro- and microscale" published in APL Photonics. The data can be used to reproduce original plots in figures 1-4 in the main text and all original plots in the suppor ...

Zenodo2024

Enhancing Efficiency of Industrially-Compatible Monolithic Perovskite/Silicon Tandem Solar Cells with Dually-Mixed Self-Assembled Monolayers

Mohammad Khaja Nazeeruddin, Peng Gao, Ye Yang, Chaohui Li

The antisolvent-assisted spin-coating still lags behind the thermal evaporation method in fabricating perovskite films atop industrially textured silicon wafers in making monolithic perovskite/silicon solar cells (P/S-TSCs). The inhomogeneity of hole-selec ...

Wiley-V C H Verlag Gmbh2024

High-Quality Data Enabling Universality of Band Gap Descriptor and Discovery of Photovoltaic Perovskites

Alfredo Pasquarello, Wei Chen, Haiyuan Wang

Extensive machine-learning-assisted research has been dedicated to predicting band gaps for perovskites, driven by their immense potential in photovoltaics. Yet, the effectiveness is often hampered by the lack of high-quality band gap data sets, particular ...

Amer Chemical Soc2024

Polarization-enhanced GaN Schottky barrier diodes: Ultra-thin InGaN for high breakdown voltage and low Ron

Elison de Nazareth Matioli, Alessandro Floriduz, Zheng Hao

In this work, we present a concept that leverages the strong piezoelectric polarization field in InGaN, which counteracts the external electric field at reverse bias. We show that despite the smaller InGaN band-gap and lower critical electric field, its st ...

2024

Font Side Solutions for c-Si Solar Cells with High-Temperature Passivating Contacts

Ezgi Genç

In this work, we studied the potential of using thin films deposited by plasma-enhanced chemical vapor deposition (PECVD) for two main purposes: introducing an n-type passivating contact at the front of a TOPCon solar cell, or simplifying the fabrication o ...

EPFL2024

Identification and Mitigation of Degradation Mechanisms Induced by Heat and Light in NiOx-based Perovskite Solar Cells

Marion Solange Madeleine Dussouillez

Perovskite solar cells (PSCs) offer an attractive solution to increase the efficiency of PV panels via perovskite/silicon tandems thanks to their potential cost-effectiveness and high efficiency. In inverted PSC architecture (p-i-n), commonly used hole con ...

EPFL2024

Plasmonically enhanced molecular junctions for investigation of atomic-scale fluctuations in self-assembled monolayers

Sakthi Priya Amirtharaj

Molecular junctions represent a fascinating frontier in the realm of nanotechnology and are one of the smallest optoelectronic devices possible, consisting of individual molecules or a group of molecules that serve as the active element sandwiched between ...

EPFL2024

Single-Mode Laser in the Telecom Range by Deterministic Amplification of the Topological Interface Mode

Kirsten Emilie Moselund, Chang Won Lee

Photonic integrated circuits are paving the way for novel on-chip functionalities with diverse applications in communication, computing, and beyond. The integration of on-chip light sources, especially single-mode lasers, is crucial for advancing those pho ...

Amer Chemical Soc2024

Structural divergence of molecular hole selective materials for viable p-i-n perovskite photovoltaics: a comprehensive review

Mohammad Khaja Nazeeruddin, Peng Gao, Paramaguru Ganesan

Perovskite solar cells (PSCs) have garnered significant attention within the photovoltaic research community due to their remarkable progress in just one decade. Among the device configurations, the p-i-n structured PSC offers several advantages, including ...

Royal Society of Chemistry2024

A Dual-Channel Gate Driver Design with Active Voltage Balancing Circuit for Series Connection of SiC MOSFETs

Drazen Dujic

Dual-channel gate driver is commonly utilized in the industry for accommodating the widespread use of half-bridge power modules. As wide-bandgap devices become increasingly prevalent due to their superior switching characteristics compared with conventiona ...

2024

Computational Studies on the Stability of Organic-Inorganic Hybrid Halide Lead Perovskites

Mathias Dankl

Perovskite-based solar cells are currently the most rapidly advancing photovoltaic technology but concerns about their long-term stability are still impeding full-scale commercialization. This thesis provides computational insights into some of the stabili ...

EPFL2024

Silicon nitride electric-field poled microresonator modulator

Camille Sophie Brès, Anton Stroganov, Edgars Nitiss, Boris Zabelich, Christian André Clément Lafforgue

Stoichiometric silicon nitride is a highly regarded platform for its favorable attributes, such as low propagation loss and compatibility with complementary metal-oxide-semiconductor technology, making it a prominent choice for various linear and nonlinear ...

2024