The new theory of compressive sensing enables direct analog-to-information conversion compressible signals at sub-Nyquist acquisition rates. authors develop theory, algorithms, performance bounds, and a prototype implementation for an converter based on random demodulation. architecture is particularly apropos wideband that are sparse in the time-frequency plane. End-to-end simulations complete transistor-level prove concept under effect circuit nonidealities.

Many problems in radar and communication signal processing involve radio frequency (RF) signals of very high bandwidth. This presents a serious challenge to systems that might attempt use high-rate analog-to-digital converter (ADC) sample these signals, as prescribed by the Shannon/Nyquist sampling theorem. In situations, however, information level is often far lower than actual bandwidth, which prompts question whether more efficient schemes can be developed for measuring such signals. this...

The remarkable potential of metasurface holography promises revolutionary advancements for imaging, chip-integrated augmented/virtual reality (AR/VR) technology, and flat optical displays. choice constituent element geometry constrains many applications purveyed through polarization-independent response. limited capabilities degree freedoms in commonly used meta-atoms restrict the design flexibility to break conventional trade-off between polarization-insensitivity bandwidth. Here, we...

The efficiency of traditional solar cells is constrained due to the Shockley-Queisser limit, circumvent this theoretical concept thermophotovoltaics (STPVs) has been introduced. typical design an STPV system consists a wideband absorber with its front side facing sun. back physically attached selective emitter low-bandgap photovoltaic (PV) cell. We demonstrate consisting and pair achieving high absorptance radiation within range 400-1500 nm (covering visible infrared regions), whereas...

Abstract Symmetric spin–orbit interaction (SOI)‐based approaches apply a practical limit on helicity multiplexed metaoptics, i.e., center symmetric information encoding. Contrarily, asymmetric SOI's based the combination of geometric and propagation phase‐delay can effectively address such limitations for multifunctional metaoptics cost design complexities. In this paper, simple SOI‐based technique is realized employing only single unit cell, breaking conventional tradeoff between complexity...

Abstract Next‐generation holographic displays have promising applications in medical science, augmented/virtual reality, smart security, data encryption, etc. Although metasurfaces emerged as the suitable choice to provide compact displays, multifunctionality at broadband optical wavelengths is inevitable for abovementioned applications. Here, a metasurface demonstrated based on chiral structures introduce terms of multiple wavefront information depending upon polarization incident light....

Smart energy has evolved over the years to include multiple domains integrated across technology themes, such as electricity, smart grid, and logistics, linked through communication processed in cloud a holistic way deliver on global challenges. Advances sensing, communication, computation technologies have been made that enable better system implementations. In systems, sensing spanned with newer techniques are more accurate, greater dynamic ranges, reliable. Similarly, now into very...

Metasurfaces have shown remarkable potential to manipulate many of light's intrinsic properties, such as phase, amplitude, and polarization. Recent advancements in nanofabrication technologies persistent efforts from the research community result realization highly efficient, broadband, multifunctional metasurfaces. Simultaneous control these characteristics a single-layered metasurface will be an apparent technological extension. Here, we demonstrate broadband platform with unprecedented...

Angle-dependent next-generation displays have potential applications in 3D stereoscopic and head-mounted displays, image combiners, encryption for augmented reality (AR) security. Metasurfaces enable such exceptional functionalities with groundbreaking achievements efficient over the past decades. However, limitations angular dispersion control make them unfit numerous nanophotonic applications. Here, we propose a spin-selective angle-dependent all-dielectric metasurface unique design...

The authors present an optical range resonator based on single mode metal-insulator-metal plasmonic gap waveguides. Complete transmission at 90° bends would enable the design of rectangular structures with cross-section area less than 500nm2, which consequently leads to easing fabrication process. exhibits a free spectral 270nm. We show that small bridge between and input waveguide can be used tune resonance frequency. In addition, ultracompact add/drop directional couplers are realizable...

We develop a framework for analog-to-information conversion that enables sub-Nyquist acquisition and processing of wideband signals are sparse in local Fourier representation. The first component the is random sampling system can be implemented practical hardware. second an efficient information recovery algorithm to compute spectrogram signal, which we dub sparsogram. A simulated frequency hopping signal operates at 33times average rate with little degradation quality

In this paper, we present a low-loss plasmonic Bragg reflector structure with high light-confinement. We show that periodic changes in the dielectric materials of metal-insulator-metal waveguides can be utilized to design efficient subwavelength reflectors and micro-cavities. FDTD simulation results designed using realistic material parameters justify transfer matrix calculations are adequate for purposes.

Single-walled carbon nanotube (SWCNT) bundles have the potential to provide an attractive solution for resistivity and electromigration problems faced by traditional copper interconnects. This paper discusses modeling of bundle resistance on-chip interconnect applications. Based on recent experimental results, authors model impact diameter contact ohmic resistance, which has been largely ignored in previous models. The results indicate that neglecting diameter-dependent nature resistances...

The private insurance sector is recognized as one of the fastest-growing industries. This rapid growth has fueled incredible transformations over past decade. Nowadays, there exist products for most high-value assets such vehicles, jewellery, health/life, and homes. Insurance companies are at forefront in adopting cutting-edge operations, processes, mathematical models to maximize profit whilst servicing their customers claims. Traditional methods that exclusively based on human-in-the-loop...

In this paper, we propose an autonomous UAV path planning framework using deep reinforcement learning approach. The objective is to employ a self-trained as flying mobile unit reach spatially distributed moving or static targets in given three dimensional urban area. approach, Deep Deterministic Policy Gradient (DDPG) with continuous action space designed train the navigate through over obstacles its assigned target. A customized reward function developed minimize distance separating and...

Secure packaging and transportation of light-sensitive chemical biomedical test tubes are crucial for environmental protection public health. Benefiting from the compact form factor high efficiency optical metasurfaces, we propose a broad-band polarization-insensitive flexible metasurface security sensitive packages in transport industry. We employ both propagation geometric phase novel TiO2 resin-based anisotropic nanoresonators to demonstrate visible domain. The ultraviolet nanoimprint...

The efficient control of optical light at the nanoscale level attracts marvelous applications, including thermal imaging, energy harvesting, photovoltaics, etc. These applications demand a high-bandwidth, thermally robust, angularly stable, and miniaturized absorber, which is key challenge to be addressed. So, in this study, simple cost-effective solution attain high-bandwidth nanostructured absorber demonstrated. designed composed plain circular ring nickel metal, possesses many interesting...

Graphene-based metamaterials are gaining popularity for developing various reconfigurable and electrically tunable optical devices – especially in terahertz (THz) infrared (IR) bands. Therefore, this paper, we aim to investigate the broadband metamaterial-based absorber that efficiently absorbs THz radiation ranging from 2.2 4.6 THz. The proposed comprises a simple meta-square ring of graphene, which possesses different slots its structure induce multiple plasmonic resonances. It is observed...

Multi-functional metasurfaces have attracted great attention due to the significant possibilities realize highly integrated and ultra-compact meta-devices. Merging nano-printing holographic information multiplexing is one of effective ways achieve multi-functionality, such a merger can increase encoding capacity. However, current approaches rely on stacking layers interleaving, where multiple resonators effectively combine different functionalities cost efficiency, design complexity,...

Abstract Futuristic holographic displays will essentially require broadband chiro‐optical effects for medical imaging, virtual reality, smart security, and optical encryption. However, conventional metasurfaces cannot provide such on‐chip realization of effects. Moreover, the simultaneous conversion amplitude, polarization, phase (APP) at wavelengths to introduce giant chirality has not been realized yet. In this paper, a planar all‐dielectric metasurface is proposed incorporating extra...

In recent years, metamaterials and metasurfaces have prospered in many fields of “science technology,” covering the entire electromagnetic spectrum. Metasurface devices constituting a set arrangement meta-atoms translate into modern-day miniaturized means to achieve planar, ultrathin, multifunctional (EM) systems. Metasurfaces are ideal candidates develop next-generation, lightweight, fabrication-friendly optical components as they impart local space-variant phase changes on incident EM...

Nanostructured-based broadband perfect absorbers are of great interest in a wide range applications, including spectroscopy, energy harvesting, and thermal photonics, etc. Here, planar square meta-ring nickel (Ni) is presented, which has the potential to absorb large operational wavelength starting from 400 nm 3000 nm. The proposed device model comprises configuration three layers with top bottom metal Ni middle dielectric layer aluminium nitride (AlN). designed ring metamaterial absorber...

Metasurfaces are composed of a two-dimensional array carefully engineered subwavelength structures. They provide novel compact alternative to conventional voluminous optical components. However, their design involves time-consuming hit and trial procedure, requiring many iterative electromagnetic simulations through expensive commercial solvers. To overcome this non-practical strategy, recently, various deep-learning-based fast low computational cost networks have been proposed optimize...

In this manuscript, a novel photonic crystal resonator (PhCR) structure having an exponentially graded refractive index profile is proposed to regulate and alter the dispersion characteristics for first time. The comprises silicon material, where porosity deliberately introduced modulate locally. structural parameters are optimized have resonant wavelength of 1550 nm. Further, impact various like incidence angle, defect layer thickness, analyte infiltration on device performance evaluated....