Publication

Photoexcited carrier relaxation dynamics in pentacene probed by ultrafast optical spectroscopy: Influence of morphology on relaxation processes

Publications associées (32)

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

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

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

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

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

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

Terahertz emission from diamond nitrogen-vacancy centers

László Forró, Ferenc Simon, Sándor Kollarics, Bence Gábor Márkus

Coherent light sources emitting in the terahertz range are highly sought after for fundamental research and applications. Terahertz lasers rely on achieving population inversion. We demonstrate the generation of terahertz radiation using nitrogen-vacancy c ...

Amer Assoc Advancement Science2024

Durable Perovskite Solar Cells with 24.5% Average Efficiency: The Role of Rigid Conjugated Core in Molecular Semiconductors

Michael Graetzel, Shaik Mohammed Zakeeruddin, Peng Wang, Felix Thomas Eickemeyer, Ming Ren

Efficient and robust n-i-p perovskite solar cells necessitate superior organic hole-transport materials with both mechanical and electronic prowess. Deciphering the structure-property relationship of these materials is crucial for practical perovskite sola ...

Wiley-V C H Verlag Gmbh2024

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

Mixed ionic-electronic conduction in Ruddlesden-Popper and Dion-Jacobson layered hybrid perovskites with aromatic organic spacers

Michael Graetzel, Davide Moia, Joachim Maier, Jovana Milic, Algirdas Ducinskas, Mina Jung

The understanding of mixed ionic-electronic conductivity in hybrid perovskites has enabled major advances in the development of optoelectronic devices based on this class of materials. While recent investigations revealed the potential of using dimensional ...

Royal Society of Chemistry2024

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

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

Investigating the Effect of Crystal Morphology on Optoelectronic Properties of Zinc Phosphide Thin Films via Optical-pump Terahertz Probe Spectroscopy

Elias Zsolt Stutz, Jean-Baptiste Leran, Léa Buswell, Mahdi Zamani, Simon Robert Escobar Steinvall, Rajrupa Paul, Mirjana Dimitrievska

Zinc phosphide ( Zn3P2) is a promising earth-abundant material for solar cell applications but calls for the further understanding of its optoelectronic properties. In this work, we perform contact-free and noninvasive optical-pump terahertz probe (OPTP) s ...

IEEE2023

Zn3P2 as an earth-abundant photovoltaic material: from growth to device

Rajrupa Paul

The development of cost-effective and earth-abundant semiconducting materials is imperative for the sustainable deployment of photovoltaic technology. Zinc phosphide (Zn3P2) is a promising candidate for terawatt-scale electricity generation. It has a near- ...

EPFL2023

Ultrafast Electron Microscopy of Nanoscale Charge Dynamics in Semiconductors

Fabrizio Carbone, Ivan Madan, Giovanni Maria Vanacore, Francesco Barantani, Ido Kaminer, Kangpeng Wang, Simone Gargiulo

The ultrafast dynamics of charge carriers in solids plays a pivotal role in emerging optoelectronics, photonics, energy harvesting, and quantum technology applications. However, the investigation and direct visualization of such nonequilibrium phenomena re ...

AMER CHEMICAL SOC2023

Charge Extraction and Recombination Dynamics of CdSe/CdTe Solar Cells Studied with Transient Photovoltage/Photocurrent Techniques

Mohammad Khaja Nazeeruddin, Iwan Zimmermann, Lei Chen

Significant advancements have been made in the development of high-performance cadmium telluride (CdTe)-based thin film solar cells. However, studies examining the transient excited-state charge dynamics, which determine the final steady-state device perfo ...

IEEE2023

Synthesis and Characterization of Functionalized Spacer Cations for the Incorporation in Layered Perovskites

Simon Nussbaum

Layered hybrid organic-inorganic perovskite (LHOIP) materials are an emerging class of semiconductors endorsed as a more stable alternative compared to the more widely investigated 3D hybrid organic-inorganic halide perovskites (HOIP). Consisting of altern ...

EPFL2023

Data-driven design of organic electronic materials

Jacob Terence Blaskovits

Singlet fission (SF) is a multiexciton-generating process whereby an excited state singlet (S1) is converted into two lower-energy triplets (T1). The inclusion of a SF-capable material into a photovoltaic device offers the potential for the absorption of p ...

EPFL2023

The nanoscale impact of individual nonradiative point defects on InGaN/GaN quantum wells

Thomas Fjord Kjaersgaard Weatherley

Today's world depends on optoelectronic devices: light-emitting diodes illuminate our houses and backlight the displays on our gadgets, while laser diodes underpin fibre-optic communication. Such optoelectronic devices rely on crystalline semiconductor het ...

EPFL2023

Chemical Trend of Nonradiative Recombination in Cu(In,Ga)Se2 Alloys

Stefano Falletta

Nonradiative recombination in Cu(In,Ga)Se2 (CIGS) solar cells has long been attributed to the antisite defects MCu (M = In, Ga), but the underlying mechanism is still elusive. Using rigorous first-principles calculations, we demonstrate that the antisites ...

American Physical Society (APS)2023

Photoelectrochemical Cell Engineering for Solar Energy Conversion

Dan Zhang

Solar energy is the most abundant energy source, harnessing solar energy holds the solution to the challenge of increasing global energy demand and reducing our dependence on fossil fuels. Photovoltaics which directly convert solar energy into electricity ...

EPFL2023