Publications associées à Low temperature resistivity, thermoelectricity, and power factor of Nb doped anatase TiO2

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

Unearthing the foundational role of anharmonicity in heat transport in glasses

The time-honored Allen -Feldman theory of heat transport in glasses is generally assumed to predict a finite value for the thermal conductivity, even if it neglects the anharmonic broadening of vibrational normal modes. We demonstrate that the harmonic app ...

Amer Physical Soc2024

Modeling and optimization of PCB coils for inductive power transfer systems

Xiaotong Du

The auxiliary power supply for medium voltage converters requires high insulation capability between the source and the load. Inductive power transfer technology, with an air gap between the primary and secondary coil, offers such high insulation capabilit ...

EPFL2024

Thermal conductivity of Li 3 PS 4 solid electrolytes with ab initio accuracy

Michele Ceriotti, Federico Grasselli

The vast amount of computational studies on electrical conduction in solid-state electrolytes is not mirrored by comparable efforts addressing thermal conduction, which has been scarcely investigated despite its relevance to thermal management and (over)he ...

Amer Physical Soc2024

Innovative thermophysical characterization of an ATF composite cladding: the case of silicon carbide

Andrea Cavaliere

Nuclear power is a powerful technology that plays an important role in the fight against climate change, and research is continuously engaged in studies that could further improve its safety. After the Fukushima accident, Accident Tolerant Fuels research h ...

EPFL2024

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

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

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

Advancing efficiency and reliability in thermal analysis of laser powder-bed fusion

Christian Leinenbach, Thomas Mayer, Rafal Wróbel

In laser based powder-bed fusion of metals (PBF-LB/M), parts are fabricated by melting layers of powder using a high-intensity laser beam. During this process, the material is exposed to rapid cooling rates and intense thermal gradients, which are the unde ...

2023

Thermal management for gas lubricated, high-speed turbomachinery

Jürg Alexander Schiffmann, Luis Eric Olmedo Ocampo, Wei Liu, Wanhui Liu

High-speed turbomachinery is commonly designed to achieve high power densities. Limited space for active cooling results in a challenging thermal management. A thermal modeling approach leveraging modern declarative programming capabilities is presented, y ...

2023

Modeling and Design Optimization of Loosely Coupled PCB Spiral Coils in Inductive Power Transfer Systems

Drazen Dujic, Xiaotong Du

There are various possibilities to realize coil winding designs for an inductive power transfer system. In order to achieve high power transfer efficiency and power density and explore trade-offs between the two, design optimization around the coil link is ...

2023

Experimental study of the hydrodynamic and thermal performances of ventilated wall structures

Mohammad Rahiminejad, Dolaana Khovalyg

The presence of a ventilated air gap behind the external cladding in a building envelope is known to have a tangible contribution to the overall performance of the wall assembly. In the present study, the hydrodynamic and thermal performances of ventilated ...

2023

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

Near-junction microfluidic cooling for high power-density GaN-on-Si electronics: A wafer, device, packaging, and system-level investigation

Remco Franciscus Peter van Erp

Electrification of the energy section, from generation to end-use, plays an essential role in reducing global CO2 emission. Innovations in power electronics are required to increase conversion efficiency and power density. Gallium nitride (GaN) transistors ...

EPFL2022

Conductive Heat Transfer in Partially Saturated Gas Diffusion Layers with Evaporative Cooling

Sophia Haussener, Mirco Magnini, Felix N. Büchi

Heat transport is an important, though often neglected function of gas diffusion layers (GDLs) of polymer electrolyte membrane fuel cells. Thermal conductivity is a key property, especially in partially water saturated GDLs and when the phase change of wat ...

2022

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

Nicola Marzari, Samuel Poncé, Changpeng Lin

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

3D printing of elastomeric mechanical sensors designed for human motion monitoring

Ryan Mitchell van Dommelen

In this thesis several advances are made to the emerging field of 3D printed mechanical sensors. Techniques and processes were developed to enable the integration of highly conductive, and capacitive and piezoresistive sensing features embedded within 3D p ...

EPFL2022

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

Development of microdevices for the in-plane thermoelectric characterization of deposited films

Stefano Mischler

Measuring the thermoelectric transport properties of a material is a prerequisite to determining its usefulness for application in waste heat recovery or cooling and the basis for devising improvement strategies. While well-established characterization met ...

ELSEVIER2021