Dielectric characterisation of polarisable particles, and prediction of the forces and torques exerted upon them, relies on the knowledge of the effective, induced dipole moment. In turn, through the mechanism of depolarisation, the induced dipole moment of a particle is strongly dependent upon its shape. Since realistic shapes create modelling difficulties, the ‘spherical particle’ approximati...

We report the ferroelectric property in Tb2Ti2O7 pyrochlore, prepared by a two-step solid-state reaction method. A concave P-E (polarisation vs electric field) loop observed from 382 K confirms ferroelectricity, below which remains as pointed or banana-shaped. Dielectric plots clearly show an anomaly at 383 and magnetic data reveals deviation 380 supporting ordering. The origin of ferroelectric...

32 Driving the interconnect dimensions of microelectronic circuits to smaller sizes, the delay time caused by the electrical resistance of the Aluminium or Copper wires and the capacitors generated by neighbouring wires and the insulating material becomes the essential limiting factor of the performance of the circuits [1-3]. Fig. 1 shows the delay time as a function of the interconnect dimensi...

When unpolarised light is reflected from a smooth dielectric surface, it becomes partially polarised. This is due to the orientation of dipoles induced in the reflecting medium and applies to both specular and diffuse reflection. This thesis aims to exploit the polarising properties of surface reflection for computer vision applications. Most importantly, the thesis proposes novel shape and ref...

BACKGROUND Animal vision spans a great range of complexity, with systems evolving to detect variations in light intensity, distribution, colour, and polarisation. Polarisation vision systems studied to date detect one to four channels of linear polarisation, combining them in opponent pairs to provide intensity-independent operation. Circular polarisation vision has never been seen, and is wide...

Polarisation control is demonstrated in circular gainguided top-surface emitting vertical cavity lasers by etching a narrow trench near the cavity aperture. An optimum etch depth exists for which all modes are pinned in a single polarisation. The etch orientation determines the dominant polarisation state of emission by modifying the spontaneous emission coupling into each polarisation state. P...

Microbial anodes were formed from compost leachate on carbon cloth electrodes. The biofilms formed at the surface of electrodes kept at open circuit contained microorganisms that switched their metabolism towards electrode respiration in response to a few minutes of polarisation. When polarisation at -0.2 V/SCE (+0.04 V/SHE) was applied to a pre-established biofilm formed at open circuit (delay...

This study is dedicated to the development of a new design shielded low-loss metal-dielectric waveguide for frequency range 90–100 GHz. High level losses in metal major challenge complicating implementation commonly used waveguides specified wavelength range. The objective was develop proposal regarding with lower than 0.5 dB/m, persistent wave polarisation. To address problem, we analysed vari...

Linear polarisation in gamma-ray burst prompt emission is an important diagnostic with the potential to significantly constrain models. The spectrometer aboard INTEGRAL, SPI, has the capability to detect the signature of polarised emission from a bright γ–ray source. GRB 041219a is the most intense burst localised by INTEGRAL with a fluence of 5.7 ×10−4 ergs cm−2 over the energy range 20 keV–8 ...