The large-scale fabrication of high-performance on-chip micro-supercapacitors (MSCs) is the footstone for development next-generation miniaturized electronic devices. In practical applications, however, MSCs may suffer from a low areal energy density as well complicated strategy that incompatible with semiconductor processing technology. Herein, we propose scalable realization silicon-based three-dimensional (3D) all-solid-state MSC via combination semiconductor-based electrode processing,...

The compressive behaviour of bonded patch repaired composite laminates is examined. A non-linear stress analysis performed on a double-lap joint in order to identify critical parameters and design an efficient external repair. It found that oversized patches not only increase the structure's weight but also concentrations region which can cause premature failure. Reducing thickness near edges overlap increasing local adhesive decreases concentration both shear peel stresses. three-...

Ultra-wideband absorbers have been extensively used in wireless communications, energy harvesting, and stealth applications. Herein, with the combination of experimental theoretical analyses, we develop a flexible ultra-wideband terahertz absorber based on vertically aligned carbon nanotubes (VACNTs). Measured results show that proposed is able to work efficiently within entire THz region (e.g., 0.1-3.0 THz), an average power absorptance >98% at normal incidence. The absorption performance...

This multidisciplinary paper reports on a research application-led study for predicting atmospheric attenuation, and tries to bridge the knowledge gap between applied engineering sciences. As useful comparative baseline, this focuses specifically attenuation under pristine conditions, over extended terahertz spectrum. Three well-known simulation software packages (`HITRAN Web', MODTRAN <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> 4,...

High-precision microelectromechanical inertial sensors based on spring-mass structures are of great interests for a wide range applications, including navigation, disaster warning and resource exploration. Lowering the resonant frequency is essential to further improve sensitivity sensors. However, conventional approaches facing insurmountable difficulties from size reduction machining precision. This paper proposed novel quasi-zero-stiffness mechanism that compatible with MEMS technologies...

The gate-type carbon nanotubes cathodes exhibit advantages in long-term stable emission owing to the uniformity of electrical field on nanotubes, but gate inevitably reduces transmittance electron beam, posing challenges for system stabilities. In this work, we introduce beam focusing technique using self-charging SiNx/Au/Si gate. potential SiNx is measured be approximately -60 V quickly after cathode turning on, negative can maintained as goes on. charged surface generates rebounding...

This work reports a multiple-parameter decoupling (MPD) method based on resonant MEMS sensors subject to blue-sideband excitation (BSE), thus enabling simultaneous separation of the cross-coupled physical quantities, e.g. acceleration and temperature, single sensor. Such technique exploits property BSE that multiple vibration modes resonator can be excited at same time. The proposed MPD algorithm is applied two distinct sensors, i.e. base-line electrostatic force sensor, vacuum-packaged...

Metamaterial-based absorbers have been extensively investigated in the terahertz (THz) range with ever increasing performances. In this paper, we propose an all-dielectric THz absorber based on doped silicon. The unit cell consists of a silicon cross resonator internal cross-shaped air cavity. Numerical results suggest that proposed can operate from to far-infrared regimes, having average power absorption ∼95% between 0.6 and 10 THz. Experimental using time-domain spectroscopy show good...

A flexible THz wave absorber based on G-VACNT hybrids is demonstrated for ultra-broadband absorption and imaging applications.

The thermal (emitted) infrared frequency bands, from 20-40 THz and 60-100 THz, are best known for applications in thermography. This underused unregulated part of the spectral range offers opportunities development secure communications. 'THz Torch' concept was recently presented by authors. technology fundamentally exploits engineered blackbody radiation, partitioning thermally-generated noise power into pre-defined channels; energy each channel is then independently pulsed modulated...

Capacitive micro accelerometers with high sensitivity have found wide applications in geophysics. Reducing the interelectrode spacing, which is determined by thickness difference between electrodes and solder bumps flip-chip eutectic bonding, an efficient way to improve of area-varying capacitive transducers accelerometers. Traditional methods require extra materials processes, precise control both pumps necessary. This work introduces a novel method for spacing using three dimensional (3D)...

Abstract High and uniform absorption capabilities of terahertz (THz) waves in an ultra‐broadband range is desirable for many THz functional devices. Nowadays, it still challenging to fabricate flexible absorbers with a uniformly high absorptance across the entire band merely based on traditional bulk materials. Engineered metamaterials utilize impedance matching reduce surface reflection at single frequency, can achieve near‐unity power within relatively narrow bandwidth. In this work,...

Capacitive displacement transducers (CDTs) have been widely used in many physical sensors, attributing to high-resolution, simple electricity and easy manufacturing process. Gap-variation CDTs generally higher resolution due small electrode gaps but suffer from the pull-in effect, nonlinear effect squeeze-film damping; whereas area-variation intrinsically good linearity much smaller slide-film damping. However, parallel-plate-based width larger than gap with negligible fringe effect;...

This paper demonstrates an ultra-low cost THz system for implementing a short-range wireless communications link in the far/mid-infrared parts of electromagnetic spectrum. The basic prototype front-end hardware is deliberately kept very simple; based around miniature incandescent light bulbs, filters and pyroelectric infrared sensors. While only low data rate has been experimentally demonstrated so far, this does not represent fundamental limitation, as number technological enhancements are...

The 'THz Torch' concept is an emerging technology that was recently introduced by the authors for implementing secure wireless communications over short distances within thermal infrared (20-100 THz, 15 μm to 3 μm). In order predict band-limited output radiated power from transmitters, first time, this paper reports on a detailed investigation into radiation mechanisms associated with basic transducer. We demonstrate how both primary and secondary sources of emitted miniature incandescent...

In this paper, we propose a metamaterial-based terahertz (THz) absorber with optically tunable absorbance. The unit cell of the structure consists cross-shaped resonator, dielectric spacing layer for wave impedance matching and high-resistivity silicon (HRS) substrate. Without illumination, acts as capacitive metal mesh filter that has minimum transmittance maximum reflectance at its resonance frequency. When HRS substrate is illuminated, conductivity increases, effectively blocking...

Nanostructured metal-based compound electrodes with excellent electrochemical activity and electrical conductivity are promising for high-performance energy storage applications. In this paper, we report an asymmetric supercapacitor based on Ti Cu coated vertical-aligned carbon nanotube cloth. The active material is achieved by in-situ functionalization using a high-temperature annealing process. Scanning transmission electron microscopy Raman spectroscopy confirm the detailed nanostructures...