Multi-spectral materials, using hybridised plasmonic and metamaterial structures, can simultaneously exhibit unique resonant phenomena over several decades of wavelengths. A multi-spectral material that combines a colour filter array terahertz absorber into single is promising prospect for coaxial imager operating in the visible, near IR, wavebands.

We simulate and measure the radiation pattern of a V-band "Bull's eye" antenna for communication between CubeSats.We also propose modification that allows beam direction to be arbitrarily chosen over ±20° range, useful swarms where CubeSats must communicate with more than one neighbour.The offers high gain in low profile, which makes it readily integrable into CubeSat chassis.We study relationship number indented rings, overall gain, emission along boresight, finding seven rings is...

A metallic photonic crystal filter has been demonstrated at terahertz frequencies, with the passband tunable over range of 365–386 GHz. Tuning is achieved by a relative lateral shift two plates. Each plate comprised orthogonal layers gratings and integral mounting lugs. The plates are micromachined from silicon wafers then coated in gold to provide electromagnetic behavior. An insertion loss 3–7 dB Q 20–30 was achieved. 140μm gave tuning 21 GHz, sensitivity 150 GHz/mm, fractional 6%.

We have fabricated terahertz wire grid polarizer and bandpass filter devices on high-density polyethylene substrates using simple photolithographic fabrication techniques. The performance of the was measured a Fourier transform IR spectrometer. Both showed good in frequency range up to 5 THz, agreement with rigorous coupled-wave analysis (polarizer) finite-difference time-domain (filter) simulations. Our results successfully demonstrate use standard techniques produce large-aperture...

We report the experimental in situ characterization of 30-40 MHz and 868 wireless transmission schemes for ingestible capsules, porcine carcasses. This includes a detailed study performance magnetically coupled near-field very high-frequency (VHF) scheme that requires only one eighth volume quarter power consumption existing 868-MHz solutions. Our measurements tested four different capsules specially constructed this (two variants each scheme), two scenarios. One mimicked body-worn receiving...

Superconducting nanowire single photon detectors are rapidly emerging as a key infrared photon-counting technology. Two front-side-coupled silver dipole nanoantennas, simulated to have resonances at 1480 and 1525 nm, were fabricated in two-step process. An enhancement of 50 130% the system detection efficiency was observed when illuminating antennas. This offers pathway increasing absorption into superconducting nanowires, creating larger active areas, achieving more efficient longer wavelengths.

A tunable metallic photonic crystal filter with a mechanical tuning mechanism is demonstrated. The performance predicted rigorous full-vector electromagnetic simulations (finite-difference time domain). prototype has been built and characterized in the W band (70–110 GHz) using vector network analyzer configured for free-space measurement of S parameters. measured filter’s passband quality factor 11, range 3.5 GHz, insertion loss only 1.1–1.7 dB. Device fabrication straightforward, yielding...

We design, fabricate and characterise a narrowband Fabry-Pérot multispectral filter set for the visible range (400-750 nm) that is suitable integration onto complementary-metal oxide-semiconductor image sensors. reduce fabrication steps by fixing physical cavity length altering effective optical instead. Using electron-beam lithography, sub-wavelength hole array patterned in silicon nitride layer, backfilled with poly(methyl methacrylate), bounded aluminium mirrors to create 23 filters...

Single-phase aluminium carbide, Al₄C₃, can be synthesised from the elements energy-efficiently in 30 min using simple multi-mode microwave techniques; syntheses are atmosphere-dependent with open reactions leading to preferential formation of oxycarbides.

We present preliminary results of the acceleration three-dimensional (3D) alternating direction implicit finite-difference time-domain (ADI-FDTD) method on graphics processor units (GPUs). Although ADI-FDTD iteration comprises two substeps, which each require solving a tridiagonal matrix system equations over xy, xz, yz planes domain, application this scheme frees time-step size from Courant-Friedrichs-Lewy stability constraint. In our implementation we took advantage fine-grain thread...

The authors present a new approach to designing V‐band Bull's eye antennas so as produce multiple beams, which are either fixed or discretely steerable. comprise concentric rings around subwavelength aperture. Beam deflection is accomplished by adjusting the effective spacing of rings, they explain in terms coupling angle free space and surface waves. They show that beams can be obtained from single antenna, with each beam being controlled independently relevant portion ring pattern....

This study focuses on the application of orbital angular momentum (OAM) modes for enhancing radio communications. It is shown that OAM can enhance spectral efficiency line‐of‐sight links where there limited or no diversity gain, and also increase physical layer security. Multiple‐input multiple‐output systems, in comparison, struggle to give improvements because they are not typically configured exploit modes. The concept specifically using shows great promise provided several challenges...

Graduates are entering a sociotechnological world, with teaching and assessment needing to reflect that, by shifting from ‘recall-on-paper’ ‘do-it-for-real’. With increasing student numbers, it is not feasible have staff-student ratios round-the-clock availability required provide instant feedback ever-more interactive sessions, so digital solutions the only option. There already growing comfort using computers in formal assessment; however, more work extend beyond performance indicators...

Multi-spectral imaging systems typically require the cumbersome integration of disparate filtering materials in order to work simultaneously multiple spectral regions.We show for first time how a single nano-patterned metal film can be used filter multi-spectral content from visible, near infrared and terahertz bands by hybridizing plasmonics metamaterials.Plasmonic structures are well-suited visible band owing resonant dielectric properties metals, whereas metamaterials preferable at...

The authors present the design and simulation of a planar Bull's eye antenna that can simultaneously produce four orbital angular momentum (OAM) modes with up to 2.4 GHz impedance bandwidth at 60 GHz. OAM l = ±3, ±13 are produced by two ring resonators in centre antenna. peak gain is 13.1 (8.1) dBi ±10 (±25) degrees for mode ±3 (±13), all over 30° range (15–45° from boresight). For reception demultiplexing, use discretely sampled partial aperture receiver (DSPAR), show algebraically such...

We describe a low-cost, open-access, CubeSat-based calibration instrument that is designed to support ground-based and sub-orbital experiments searching for various polarization signals in the cosmic microwave background (CMB). All modern CMB require robust program will allow effects of instrument-induced be mitigated during data analysis. A bright, compact, linearly polarized astrophysical source with properties known adequate precision does not exist. Therefore, we space-based...

Line edge roughness (LER) in end-of-the-roadmap integrated circuit interconnects causes variability their resistance R, capacitance C and hence also RC delay. We present an analysis of LER-induced resistance, delay short-range within standard cells at the 32, 22 18 nm technology nodes using both a commercial extraction tool as well fast quasi-analytical (QA) method. Our QA method includes size dependent resistivity which, when coupled with LER, reveals increased total these nodes. For...

This paper evaluates the performance of three-dimensionally (3D) printed spiral phase plates (SPPs) for enabling an orbital angular momentum (OAM) multiplexed radio system. The design and realization SPPs by means additive manufacturing exploiting a high-permittivity material is described. Modes 1 2 are then evaluated at 15 GHz in terms 3D complex radiation pattern, mode purity beam collimation dielectric lens. results with lens yield crosstalk −8 dB between modes −1, −11.4 −2. We suggest...

The designs of many student-facing learning analytics (SFLA) dashboards are insufficiently informed by educational research and lack rigorous evaluation in authentic contexts, including during remote laboratory practical work. We present evaluate an SFLA dashboard designed using the principles formative assessment to provide feedback students lab activities. Feedback is based upon graphical visualisations student actions performed tasks comparison expected procedures TaskCompare - our...

This letter studies the possibilities of manufacturing copper-based passive ultrahigh frequency (UHF) radio identification (RFID) tags using inkjet and thermal printing on two substrate materials, polyimide (Kapton), a polyester-based (Flexcon THERMLfilm). Both methods are tested to fabricate different tag designs, performance successfully printed is evaluated wireless measurements. Measurement results show that both methods, while copper material, can be used effectively UHF RFID antennas...

Diode‐switching that can be used to introduce frequency agility into antennas produced by thermal transfer printing is demonstrated. The particular example a triangular Sierpinski fractal pattern with two PIN diodes switch between operation optimised for the 800 MHz ultra‐high (UHF) band (diodes on) and 2400 ISM off). Our measured results show an improvement in S 11 UHF from −2 −28 dB −7 −30 at MHz, when switching appropriately. bandwidth 200 (1000) directivity 3.1 (5.2 dB) while gain −5.2...