Abstract Ferroelectret nanogenerators were recently introduced as a promising alternative technology for harvesting kinetic energy. Here we report the device’s intrinsic properties that allow bidirectional conversion of energy between electrical and mechanical domains; thus extending its potential use in wearable electronics beyond power generation realm. This electromechanical coupling, combined with their flexibility thin film-like form, bestows dual-functional transducing capabilities to...

Engineered metamaterials offer unique functionalities for manipulating the spectral and spatial properties of electromagnetic waves in unconventional ways. Here, we report a novel approach making reconfigurable metasurfaces capable deflecting an electronically controllable fashion. This is accomplished by tilting phase front through two-dimensional array resonant metasurface unit-cells with electronically-controlled phase-change materials embedded inside. Such can be placed at output facet...

There is an increasing interest in the development of memristive or artificial synaptic devices that emulate neuronal activities for neuromorphic computing applications. While there have already been many reports on transistors implemented rigid substrates, use flexible could potentially enable even broader range In this paper, we report thin-film built ultrathin substrate using high carrier mobility semiconducting single-wall carbon nanotubes. The characteristics transistor including...

This study demonstrates the use of light colors to selectively actuate micrometer-sized structures.

This paper describes a strategy to impart brittle conductive patterns composed of silver nanoparticles with high stretchability and structure‐dependent electrical characteristics. Silver nanoinks are printed on an elastomeric polyurethane acrylate substrate in the form planar serpentine structures that can effectively mitigate strain concentration. The relative changes resistance (∆ R / 0 ) found strongly depend radius ( r determines relieving efficiency. Features small curvature show...

A MEMS reconfigurable ultra-wideband (UWB) antenna that rejects on-demand all WLAN signals in the entire 5.15 to 5.825 GHz range (675 MHz bandwidth) is presented. The design, miniaturization procedure, and monolithic integration with biasing network on SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Quartz substrate are described. challenges addressed work presented a way useful for engineers. method vary rejection bandwidth also...

As the initial stage in formation of human intelligence, sensory–memory system plays a critical role for being to perceive, interact, and evolve with environment. Electronic implementation such biological empowers development environment-interactive artificial intelligence (AI) that can learn diversified external information, which could potentially broaden application AI technology field human–computer interaction. Here, we report multimodal consisting sensors generating biomimetic visual,...

The curvature of VO2-coated silicon microcantilevers was measured as the temperature cycled through coating’s insulator-to-metal transition (IMT), which drives change mainly strain generated during this reversible structural transformation. films were grown by pulsed laser deposition (PLD) on heated substrates. Cantilever tip displacement for a 130 μm long cantilever changed recording deflection beam, and estimated film stress calculated from data. A in over 2000 m−1 observed narrow range...

Vanadium dioxide exhibits a well-known insulator-to-metal transition during which several of its physical properties change significantly. A hysteresis loop develops for each them as the material is heated and then cooled through transition. In this work VO2/SiO2 samples were maintained—by heat sinking—at selected temperature within heating branch loops resistance near-infrared transmittance, while brief thermal excursions VO2 film caused by either voltage pulses applied to or laser light...

Vanadium dioxide (VO2)-based actuators have demonstrated great performance in terms of strain energy density, speed, reversible actuation, programming capabilities, and large deflection. The relative low phase transition temperature VO2 (∼68 °C) gives this technology an additional advantage over typical thermal power consumption. However, can be further improved if light absorption is enhanced. Here we report a VO2-based actuator that incorporates single-wall carbon nanotubes (SWNTs) as...

Silicon microcantilevers were coated by pulsed laser deposition with vanadium dioxide (VO2) (monoclinic M1 phase) and V1−xCrxO2 x near 0.024 M2 phase), their mechanical characteristics studied as a function of temperature through the films’ insulator-to-metal transition (IMT). The undoped VO2 films grew (011)M1 planes parallel to substrate, while Cr-doped oriented (201)M2 (2¯01)M2 substrate. In both cases, transformed reversibly IMT tetragonal (rutile, R) phase, film (110)R fundamental...

Abstract Photoinduced threshold switching processes that lead to bistability and the formation of metastable phases in photoinduced phase transition VO 2 are elucidated through ultrafast electron diffraction diffusive scattering techniques with varying excitation wavelengths. We uncover two distinct regimes dynamical change: a nearly instantaneous crossover into an intermediate state its decay led by lattice instabilities over 10 ps timescales. The structure this is identified be monoclinic,...

The integration of VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> thin films in a MEMS actuator device is presented. structural phase transition was induced electro-thermally by resistive heaters monolithically integrated the actuator. drastic mechanical displacements generated large stress during film have been characterized for static and time-dependent current pulses to heater, air vacuum environments. A comprehensive simplified...

A new method to reconfigure, tune or program an antenna is presented and validated through a fabricated proof-of-concept prototype. The relies on the changing electrical properties of smart material, vanadium dioxide ( VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ), across its solid-to-solid phase transition. change in material induced thermally. developed device monolithically integrated -based that changes resonant frequency...

We present a comprehensive study of new method to reconfigure, tune, and/or program antennas and radio-frequency (RF) devices. The consists using electrical signals induce the solid-tosolid phase transition in vanadium dioxide (VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) thin-film patterned structures that connect device metallization layer with extensions, thus effectively changing geometry device. Applied voltage pulses...

Young’s modulus of VO2 thin films has been measured for the first time through material’s insulator-to-metal transition. The resonant frequency silicon coated cantilevers was in temperature range 30–90°C. It found that during semiconductor to metallic transition films, which occurs at a 68°C, changes most dramatically with temperature, abruptly reversing its declining trend increasing temperature. film is stiffened and, as further raised, reasserted similar rate.

Vanadium dioxide ( <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${\rm VO_2}$</tex></formula> ) undergoes a thermally induced solid-to-solid phase transition, which can be exploited for actuation purposes. -coated silicon cantilevers demonstrate abrupt curvature changes when their temperature is varied across the transition. Unlike monotonic hysteresis phenomena observed in many other smart...

Vanadium dioxide (VO ) 2 , a promising multifunctional smart material, has shown strong promise in microactuation, memory, and optical applications. During thermally induced insulator-tometal phase transition of VO2, the changes its electrical, mechanical, properties demonstrate pronounced, complex hysteresis with respect to temperature, which presents challenge utilization this material. In paper, an extended generalized Prandtl– Ishlinskii model is proposed where nonlinear memoryless...

Applying flexible materials for energy scavenging from ambient mechanical vibrations is a clean solution that can help alleviate electrical power demands in portable devices and wearable electronics. This work presents fundamental studies on ferroelectret polymer with strong piezoelectric effect its interface self-powered storage systems. A single-layered device thickness of 80 μm was used characterizing the device's output voltage, current, transferred charge, conversion efficiency. The...

Abstract The present work demonstrates the development of a flexible, self-powered sensor patch that can be used to estimate angular acceleration and velocity, which are two essential markers for predicting concussions. device monitors dynamic strain experienced by neck through thin, polypropylene-based ferroelectret nanogenerator produces voltage pulse with profile proportional strain. intrinsic property this convert mechanical input electrical output, along its flexibility $$\sim$$...