Publications associées à A study of the phase diagram of (K,Na,Li)NbO3 determined by dielectric and piezoelectric measurements, and Raman spectroscopy

Publications associées (28)

CMOS-Compatible Antiferroelectric-Dielectric Capacitors for Multifunctional Energy Storage and Tunable Electronics

Hung-Wei Li, Mihai Adrian Ionescu, Igor Stolichnov, Niccolò Martinolli, Cyrille Masserey

This work presents a CMOS-compatible multilayer platform integrating energy storage and tunable varactor functionality within a compact system. By co-integrating antiferroelectric (AFE) and dielectric (DE) layers, the design achieves tunability up to 28%, ...

IEEE2025

Radiation Efficiency and Gain Bounds for Microstrip Patch Antennas

Anja Skrivervik

This article presents bounds on radiation efficiency and gain for microstrip patch antennas, demonstrating close alignment with the performance of classic antenna designs. These bounds serve as effective benchmarks for assessing antenna performance and eva ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2025

Elastomers Based on Polynorbornene with Polar Polysiloxane Brushes for Soft Transducer Applications

Frank Nüesch, Yeerlan Adeli

Elastomers based on cross-linked bottlebrush polymers combine an extreme softness at low strains with a strain-stiffening effect, which makes them attractive as active components in dielectric elastomer actuators (DEA). Their main disadvantage concerns the ...

Wiley-VHCA AG2024

Inversing the actuation cycle of dielectric elastomer actuators for a facial prosthesis

Yves Perriard, Yoan René Cyrille Civet, Paolo Germano, Thomas Guillaume Martinez, Stefania Maria Aliki Konstantinidi, Alexis Boegli, Quentin Philippe Mario De Menech

Dielectric Elastomer Actuators (DEAs) are a type of smart material described as compliant capacitors. They show impressive performances as soft actuators, such as a high strain and fast response. Nonetheless, replicating natural muscle function with DEAs h ...

Society of Photo-Optical Instrumentation Engineers (SPIE)2024

Positivity bounds on electromagnetic properties of media

Oliver Paul C. Janssen

We study the constraints imposed on the electromagnetic response of general media by microcausality (commutators of local fields vanish outside the light cone) and positivity of the imaginary parts (the medium can only absorb energy from the external field ...

Springer Nature2024

Toward Metantennas: Metamaterial-Based Antennas for Wireless Communications

Yuanyan Su

Antennas have historically been the most common electromagnetic (EM) technology for wireless communication systems. Antenna as hardware is entirely dependent on the EM properties of the materials used, mostly related to the permittivity and permeability. I ...

Ieee-Inst Electrical Electronics Engineers Inc2023

On-Demand Cross-Linkable Bottlebrush Polymers for Voltage- Driven Artificial Muscles

Frank Nüesch, Francis Owusu, Yeerlan Adeli

Dielectric elastomer actuators (DEAs) generate motion resembling natural muscles in reliability, adaptability, elongation, and frequency of operation. They are highly attractive in implantable soft robots or artificial organs. However, many applications of ...

AMER CHEMICAL SOC2023

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

Inflight Microwave Drying Process of Micro-droplets for High Resolution 3D printing

Kwanghoon Choi

A new Additive-Manufacturing (AM) or 3D printing concept is proposed to improve the printing resolution for metal additive manufacturing in the frame of the SFA-AM project, Powder Focusing for Beam-Induced Laser 3D Printing. The project aims to transport s ...

EPFL2022

Induced giant piezoelectricity in centrosymmetric oxides

Paul Muralt, Dragan Damjanovic, Vasiliki Tileli, Mahmoud Hadad, 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

Intrinsic switching in Si-doped HfO2: A study of Curie-Weiss law and its implications for negative capacitance field-effect transistor

Mihai Adrian Ionescu, Igor Stolichnov, Ali Saeidi, Matteo Cavalieri, Teodor Rosca, Carlotta Gastaldi, Sadegh Kamaei Bahmaei, Eamon Patrick O'Connor

HfO2-based ferroelectrics are considered a promising class of materials for logic and memory applications due to their CMOS compatibility and ferroelectric figures of merit. A steep-slope field-effect-transistor (FET) switch is a device for logic applicati ...

AMER INST PHYSICS2021

Homogenization theory for the effective permittivity of a turbulent tokamak plasma in the scrape-off layer

Stefano Alberti, Ivo Furno, Oulfa Chellaï

There has been a growing interest, over the past few years, on understanding the effect on radio frequency waves due to turbulence in the scrape-off layer of tokamak plasmas. While the far scrape-off layer density width is of the order of centimetres in co ...

Cambridge University Press2018

Breakdown of Optical Phonons' Splitting in Two-Dimensional Materials

Nicola Marzari, Marco Gibertini, Thibault Daniel Pierre Sohier

We investigate the long-wavelength dispersion of longitudinal and transverse optical phonon modes in pillar two-diinensional materials, mriltilayers, and their heterostructures. Using analytical models and density-functional perturbation theory in a two-di ...

Amer Chemical Soc2017

Diminishing SAR for Wearable UHF Antennas

Anja Skrivervik, Jovanche Trajkovikj

This letter presents a study on the specific absorption rate (SAR) evaluation of UHF wearable antennas. A planar inverted-F antenna (PIFA) intended to operate in wireless body area networks (WBANs) is taken as an example for the investigation. The presence ...

Institute of Electrical and Electronics Engineers2015

Charge-transport properties of monolayer MoS2 at the interface with dielectric materials

Simone Bertolazzi

Two-dimensional (2D) semiconductors, consisting of single-sheets of layered transition metal dichalcogenides (TMD), are attracting enormous interest from both fundamental science and technology. Monolayer molybdenum disulfide (MoS2), a typical example from ...

EPFL2015

PZT thin films for MEMS devices : from in-situ sputter deposition to energy harvesting device

Andrea Mazzalai

The recent progress in synthesis and integration of highly piezoelectric lead-zirconate-titanate (PZT) thin films onto silicon substrates are paving the way for new, more efficient and faster devices in micro electro-mechanical systems (MEMS). In compariso ...

EPFL2014

Comparison of Lead Zirconate Titanate Thin Films for Microelectromechanical Energy Harvester With Interdigitated and Parallel Plate Electrodes

Paul Muralt, Andrea Mazzalai, Nachiappan Chidambaram, Davide Balma

Lead zirconate titanate (PZT) thin films on insulator-buffered silicon substrates with interdigitated electrodes (IDEs) have the potential to harvest more energy than parallel plate electrode (PPE) structures because the former exploit the longitudinal pie ...

Ieee-Inst Electrical Electronics Engineers Inc2013

Polarization screening in polymer ferroelectric films: Uncommon bulk mechanism

Nava Setter, Alexander Tagantsev, Igor Stolichnov

Charge compensation at the interface is a fundamental phenomenon determining the operation conditions of thin-film devices incorporating ferroelectrics. The underlying mechanisms have been thoroughly addressed in perovskite ferroelectrics where the charge ...

American Institute of Physics2012

Lead-Free Relaxor-Like 0.75Bi0.5K0.5TiO3– 0.25BiFeO3 Ceramics with Large Electric Field-Induced Strain

Dragan Damjanovic

Dense and phase-pure ferroelectric ceramics of 75 mol.% Bi0.5K0.5TiO3 - 25 mol.% BiFeO3 are prepared by the conventional solid state reaction method. Their crystal structure is analyzed and discussed. The dielectric and piezoelectric properties of the cera ...

Taylor & Francis2012

Revised self-consistent continuum solvation in electronic-structure calculations

Nicola Marzari, Oliviero Andreussi

The solvation model proposed by Fattebert and Gygi [J. Comput. Chem. 23, 662 (2002)] and Scherlis et al. [J. Chem. Phys. 124, 074103 (2006)] is reformulated, overcoming some of the numerical limitations encountered and extending its range of applicability. ...

2012