Publications associées à Flexoelectric effect in finite samples

Pyroelectricity in poled all-organic polar polynorbornene/polydimethylsiloxane-based stretchable electrets

Pyroelectricity in a recently developed all-organic composite electret with a polar polynorbornene-based filler and polydimethylsiloxane (PDMS) matrix has been studied with the help of thermal and dielectric techniques. Measurement of the pyroelectric p co ...

Royal Society of Chemistry2024

Automated all-functionals infrared and Raman spectra

Nicola Marzari, Lorenzo Bastonero

Infrared and Raman spectroscopies are ubiquitous techniques employed in many experimental laboratories, thanks to their fast and non-destructive nature able to capture materials' features as spectroscopic fingerprints. Nevertheless, these measurements freq ...

Nature Portfolio2024

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

Synthesis of polysiloxane elastomers modified with sulfonyl side groups and their electromechanical response

Holger Frauenrath, Yauhen Sheima

Dielectric elastomer transducers are elastic capacitors that respond to mechanical or electrical stress. They can be used in applications such as millimeter-sized soft robots and harvesters of the energy contained in ocean waves. The dielectric component o ...

Royal Society of Chemistry2023

How to Make Elastomers Piezoelectric?

Frank Nüesch, Francis Owusu

Piezoelectrics play a significant role in modern electronics and electric devices. Thermal or mechanical stress on such materials induces a change in polarization generating an electric response, which is the sole effect of why they are so interesting. How ...

Wiley2023

Dataset for "Low-temperature processing of screen-printed piezoelectric KNbO3 with integration onto biodegradable paper substrates"

Luis Guillermo Villanueva Torrijo, Danick Briand, Morgan Mc Kay Monroe

This data set contains the data collected during the FNS project Green Piezo (Grant no. 179064) in association with the recent publication entitled “Low-temperature processing of screen-printed piezoelectric KNbO3 with integration onto biodegradable paper ...

Zenodo2023

Low-temperature processing of screen-printed piezoelectric KNbO3 with integration onto biodegradable paper substrates

Luis Guillermo Villanueva Torrijo, Danick Briand, Morgan Mc Kay Monroe

The development of fully solution-processed, biodegradable piezoelectrics is a critical step in the development of green electronics towards the worldwide reduction of harmful electronic waste. However, recent printing processes for piezoelectrics are hind ...

2023

Bottlebrush Dielectric Elastomers with Improved Properties for Actuation

Yeerlan Adeli

Dielectric elastomer actuators (DEA) are elastic capacitors composed of a pair of compliant electrodes and a soft dielectric elastomer film sandwiched in between. This kind of stretchable capacitors can be actuated when charged, can generate electricity fr ...

EPFL2023

A 5G n77 Filter Using Shear Bulk Mode Resonator With Crystalline X-cut Lithium Niobate Films

Luis Guillermo Villanueva Torrijo, Florian Fernand Hartmann

This paper presents the use of a shear bulk acoustic mode resonator made of a membrane of X-cut lithium niobate (LiNbO3) for ultra-wide band filter applications. Aluminum interdigitated (IDT) electrodes are deposited on top of the LiNbO3 thin film as well ...

IEEE2023

Nonlinear electro-mechanical coupling and thermally stimulated currents in relaxor ferroelectrics

Lukas Riemer

In this work, the emergence of polarization and electro-mechanical coupling in Pb(Mg1/3Nb2/3)O3 and Pb(Mg1/3Nb2/3)O3 â PbTiO3 was investigated by means of thermally stimulated current, and nonlinear dielectric and electro-mechanical measurements. The pre ...

EPFL2022

Stress effects on the impedance and ferroelectricity of PVDF-BiFeO3-MWCNT films using xanthan gum as dispersant

Frank Nüesch, Francis Owusu

Composite films based on dispersions of bismuth ferrite (BiFeO3) in polyvinylidene fluoride (PVDF) matrixes were prepared in the presence of multiwalled-carbon-nanotubes (MWCNT), using xanthan gum (XG) as dispersant. Films were prepared by spin coating and ...

ELSEVIER SCIENCE SA2022

High Permittivity Siloxanes as Promising Materials for Dielectric Elastomer Transducers: From Synthesis to Application

Yauhen Sheima

The speed of change in the modern world is impressive. Within the last 50 years, many devices and technologies have significantly transformed their appearance, intrinsic characteristics and improved their performance. Computers have changed from the size o ...

EPFL2022

Induced giant piezoelectricity in centrosymmetric oxides

Dragan Damjanovic, Paul Muralt, Mahmoud Hadad, Vasiliki Tileli, Lukas Riemer, Daesung Park

Piezoelectrics are materials that linearly deform in response to an applied electric field. As a fundamental prerequisite, piezoelectric materials must have a noncentrosymmetric crystal structure. For more than a century, this has remained a major obstacle ...

American Association for the Advancement of Science2022

Dielectric properties of 3-3 flexible composites by infiltration of elastomers into porous ceramic structures using cellulose scaffold

Frank Nüesch, Thomas Geiger

Elastomer composites are prepared by infiltrating polydimethylsiloxane (PDMS) into a porous ceramic structure of nanoparticles. This method differs from the conventional approach, where particles are dispersed into the polymer matrix, since here, the polym ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Stretchable High Response Piezoelectric Elastomers Based on Polable Polynorbornene Fillers in a Polydimethylsiloxane Matrix

Frank Nüesch, Francis Owusu

To advance the field of piezoelectrics, it is desirable to find materials that combine high piezoelectricity with high elasticity. Applications such as self-sensors, stretchable electronics, soft robots, and energy harvesting would benefit tremendously. Ho ...

WILEY-V C H VERLAG GMBH2022

Transient Elastomers with High Dielectric Permittivity for Actuators, Sensors, and Beyond

Holger Frauenrath, Yauhen Sheima

Dielectric elastomers (DEs) are key materials in actuators, sensors, energy harvesters, and stretchable electronics. These devices find applications in important emerging fields such as personalized medicine, renewable energy, and soft robotics. However, e ...

AMER CHEMICAL SOC2022

Negative Capacitance in HfO2 Gate Stack Structures With and Without Metal Interlayer

Igor Stolichnov, Mihai Adrian Ionescu, Ali Saeidi, Francesco Bellando, Matteo Cavalieri, Eamon Patrick O'Connor, Carlotta Gastaldi

In this work, we experimentally explore and compare FET gate stacks with and without an inner metal plane between a linear dielectric (SiO2) and a ferroelectric layer (Si-doped HfO2) operating in the negative capacitance (NC) regime. The use of nanosecond- ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Reduced material loss in thin-film lithium niobate waveguides

Tobias Kippenberg, Di Zhu, Guanhao Huang, Mikhail Churaev, Zihan Li

Thin-film lithium niobate has shown promise for scalable applications ranging from single-photon sources to high-bandwidth data communication systems. Realization of the next generation high-performance classical and quantum devices, however, requires much ...

AIP Publishing2022

Runaway dynamics in tokamak disruptions with current relaxation

The safe operation of tokamak reactors requires a reliable modelling capability of disruptions, and in particular the spatio-temporal dynamics of associated runaway electron currents. In a disruption, instabilities can break up magnetic surfaces into chaot ...

Cambridge University Press2022

Ferroelectric Effects Probed by in situ Transmission Electron Microscopy

Reinis Ignatans

Ferroelectric perovskite oxides are widely used in sensors, actuators and optical modulators and, at the same time, they show promise for implementation in future applications such as energy storage, memory and cooling devices. At the infancy of the discov ...

EPFL2022