Publications associées à Thermoélectricité

Thermoelectric power of overdoped Tl2201 crystals: charge density waves and T1 and T2 resistivities

We report measurements of the in-plane thermoelectric power (TEP) for an overdoped (OD) crystal of the single layer cuprate superconductor Tl2Ba2CuO6+x (Tl2201) at several hole concentrations (p), from 300 or 400 K to below the superconducting transition t ...

Iop Publishing Ltd2024

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

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

Controlling On-Surface Photoactivity: The Impact of π-Conjugation in Anhydride-Functionalized Molecules on a Semiconductor Surface

Karl-Heinz Ernst, Christian Wäckerlin

On-surface synthesis has become a prominent method for growing low-dimensional carbon-based nanomaterials on metal surfaces. However, the necessity of decoupling organic nanostructures from metal substrates to exploit their properties requires either trans ...

Wiley-VCH Verlag GmbH2024

Investigation of thermoelectric nanomaterials

David Thomas Osenberg

Thermoelectric conversion remains an active research field in light of its potential to enhance energy efficiency by waste heat recovery in a noise and wear-free manner. Nanostructuring is responsible for most of the recently reported improvements of the ...

EPFL2023

Effect of a temperature gradient on the screening properties of ionic fluids

Andrea Grisafi, Federico Grasselli

The electrostatic screening properties of ionic fluids are of paramount importance in countless physical processes. Yet the screening behavior of ionic conductors out of thermal equilibrium has to date mainly been studied in the context of thermoelectric p ...

AMER PHYSICAL SOC2023

Long-range electrostatic contribution to electron-phonon couplings and mobilities of two-dimensional and bulk materials

Nicola Marzari, Marco Gibertini, Samuel Poncé, Massimiliano Stengel

Charge transport plays a crucial role in manifold potential applications of two-dimensional materials, in-cluding field-effect transistors, solar cells, and transparent conductors. At most operating temperatures, charge transport is hindered by scattering ...

AMER PHYSICAL SOC2023

Plasmonic Nanofluids: Enhancing Photothermal Gradients toward Liquid Robots

Giulia Tagliabue, Matteo Bevione

In situ energy generation in soft, flexible, autonomous devices is challenging due to the need for highly stretchable and fault-resistant components. Nanofluids with pyro-, tribo-, or thermoelectric properties have recently emerged as promising solutions f ...

Amer Chemical Soc2023

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

Atomic-scale Characterization of Strain and Gate effects on Two-dimensional Materials by Scanning Tunneling Microscopy

Jz -Yuan Juo

Strain is an inevitable phenomenon in two-dimensional (2D) material, regardless of whether the film is suspended or supported. Moreover, strain is known to alter the physical and chemical properties, such as the band gap, charge carrier effective masses, d ...

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

A Triethyleneglycol C-60 Mono-adduct Derivative for Efficient Electron Transport in Inverted Perovskite Solar Cells

Mohammad Khaja Nazeeruddin, Konstantina Kalliopi Armadorou, Tobias Seewald

Inverted perovskite solar cells (PSCs) have attracted increasing attention in recent years owing to their low-temperature fabrication proces s. However, they suffer from a limited number of electron transport materials available with [6,6]-phenyl C-61 buty ...

WILEY-V C H VERLAG GMBH2023

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

Large Anomalous Nernst Angle in Co2MnGa Thin Film

Jean-Philippe Ansermet, Haiming Yu, Simon Granville, Junfeng Hu, Yao Zhang, Song Liu

The new trends for anomalous Nernst effect (ANE)-based thermoelectric devices require materials with large ANE values to realize the scalable generation of voltage. Recently, very large ANE values have been observed in single crystals of some novel magneti ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Wigner Formulation of Thermal Transport in Solids

Nicola Marzari, Michele Simoncelli

Two different heat-transport mechanisms are discussed in solids. In crystals, heat carriers propagate and scatter particlelike as described by Peierls's formulation of the Boltzmann transport equation for phonon wave packets. In glasses, instead, carriers ...

American Physical Society2022

General invariance and equilibrium conditions for lattice dynamics in 1D, 2D, and 3D materials

Nicola Marzari, Changpeng Lin, Samuel Poncé

The long-wavelength behavior of vibrational modes plays a central role in carrier transport, phonon-assisted optical properties, superconductivity, and thermomechanical and thermoelectric properties of materials. Here, we present general invariance and equ ...

NATURE PORTFOLIO2022

Construction of Fe3O4 bridged Pt/g-C3N4 heterostructure with enhanced solar to fuel conversion

Michael Graetzel, Shaik Mohammed Zakeeruddin

In this study, we report the effects of co-catalysts of Pt nanoparticles and Fe3O4 clusters on photocatalytic behaviors of g-C3N4 (CN) and the use of the resulting photocatalyst for CO2 photoreduction to solar fuels in a flow reactor operated at room-tempe ...

ELSEVIER2022

Strong temperature-dependent thermoelectric power of IrMn(3)thin films of different thicknesses

Jean-Philippe Ansermet, Haiming Yu, Junfeng Hu, Mukund Krishna Kothari

IrMn(3)thin films were experimentally characterized by thermoelectric power and resistivity as a function of temperature and sample thickness. The Seebeck coefficient shows strong temperature dependence and the value increases with temperature up to 350 K. ...

IOP PUBLISHING LTD2021

Cu/Metal Oxide Hybrid Nanocrystals as Electrocatalysts for the CO2 Reduction Reaction

Seyedehbehnaz Varandili

The electrochemical CO2 reduction reaction (CO2RR) is envisioned to play a significant role in achieving carbon neutrality while contributing to storing renewable energies. Cu-based materials are among the most promising electrocatalysts. However, 16 diffe ...

EPFL2021

Thermal transport beyond Fourier, and beyond Boltzmann

Michele Simoncelli

Crystals and glasses exhibit fundamentally different heat conduction mechanisms: the periodicity of crystals allows for the excitation of propagating vibrational waves that carry heat, as first discussed by Peierls in 1929, while in glasses the lack of per ...

EPFL2021