Publications related to Piezoresistivity and Strain-induced Band Gap Tuning in Atomically Thin MoS2

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

Strain engineering and strain measurement by spring tethers on suspended epitaxial GaN-on-Si photonic crystal devices

Romuald Houdré, Jun Wang

Suspended epitaxial gallium nitride (GaN) on silicon (Si) photonic crystal devices suffer from large residual tensile strain, especially for long waveguides, because fine structures tend to crack due to large stress. By introducing spring-like tethers, des ...

Iop Publishing Ltd2024

Towards Scalable Electronics: Synthetic 2D Materials for Large-Area 2D Circuit Integration

Zhenyu Wang

In the past decades, a significant increase of the transistor density on a chip has led to exponential growth in computational power driven by Moore's law. To overcome the bottleneck of traditional von-Neumann architecture in computational efficiency, effo ...

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

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

Hybrid organic/metal-oxide shells on semiconductor nanocrystals via colloidal atomic layer deposition

Ona Segura Lecina

The escalating energy demand and the imperative necessity to reduce the carbon footprint require transformative approaches to energy conversion. Materials chemistry plays a pivotal role in addressing these global challenges by developing novel materials fo ...

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

Improving the photoelectrocatalytic efficiency of CuWO4 through molybdenum for tungsten substitution and coupling with BiVO4

Kevin Sivula, Annalisa Polo

A systematic investigation on the photoelectrocatalytic (PEC) performance of a series of CuW1-xMoxO4 materials with different Mo for W substitution (x = 0-0.8), successfully synthesized as single, transparent photoactive layers, allowed us to identify copp ...

Royal Soc Chemistry2024

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

Dataset to accompany publication "Quantum-mechanical effects in photoluminescence from thin crystalline gold films"

Giulia Tagliabue, Fateme Kiani Shahvandi, Theodoros Tsoulos, Alan Richard Bowman

This dataset accompanies the publication "Quantum-mechanical effects in photoluminescence from thin crystalline gold films" published in Light: Science & Applications (https://doi.org/10.1038/s41377-024-01408-2). The data can be used to reproduce plots 1-4 ...

Zenodo2024

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

Quantum-mechanical effects in photoluminescence from thin crystalline gold films

Giulia Tagliabue, Fateme Kiani Shahvandi, Theodoros Tsoulos, Alan Richard Bowman

Luminescence constitutes a unique source of insight into hot carrier processes in metals, including those in plasmonic nanostructures used for sensing and energy applications. However, being weak in nature, metal luminescence remains poorly understood, its ...

2024

Interfacial engineering through lead binding using crown ethers in perovskite solar cells

Jun Ho Yum, Kevin Sivula, Jiyoun Seo, Jovana Milic, Yeonju Kim

In the domain of perovskite solar cells (PSCs), the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions. This study pioneers an approach that not only rectifies lea ...

Elsevier2024

Alleviating nanostructural phase impurities enhances the optoelectronic properties, device performance and stability of cesium-formamidinium metal-halide perovskites

Christophe Ballif, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Beat Ruhstaller, Mostafa Rabie Shlaly Bahr Othman, Daniel Anthony Jacobs, Christian Michael Wolff, Anaël Morgane Jaffrès, Austin George Kuba

The technique of alloying FA+ with Cs+ is often used to promote structural stabilization of the desirable alpha-FAPbI3 phase in halide perovskite devices. However, the precise mechanisms by which these alloying approaches improve the optoelectronic quality ...

Royal Soc Chemistry2024

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

Magneto-Thermoelectric Transport in Graphene Quantum Dot with Strong Correlations

Oleksandr Kriuchkov

Disorder at etched edges of graphene quantum dots (GQD) enables random all-to-all interactions between localized charges in partially filled Landau levels, providing a potential platform to realize the Sachdev-Ye-Kitaev (SYK) model. We use quantum Hall edg ...

2024

Two-dimensional quasi-static delamination in composite laminates under Mode-I and Mode-II conditions

Congzhe Wang

Fiber-polymer composites consist of a polymer matrix and reinforcing fibers made of various materials. These composites exhibit exceptional properties, such as a high strength-to-weight ratio and excellent corrosion resistance, which has led to their incre ...

EPFL2024

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

Data-Intensive Exploration of the Photoelectrochemical Responses of Main-Group Metal Sulfides

Nicola Colonna

Materials that efficiently promote the thermodynamically uphill water-splitting reaction under solar illumination are essential for generating carbon-free ("green") hydrogen. Mapping out the combinatorial space of potential photocatalysts for this reaction ...

Amer Chemical Soc2024