Professor John Gregg

Abstract:

Apparatus comprising: a radio frequency (RF) Robinson oscillator comprising: a resonator comprising a sensor rhumbatron, the sensor rhumbatron comprising a cavity member, the cavity member having a re-entrant boss member, the re-entrant boss member being arranged to project into a cavity portion …

Abstract:

A rotor blade sensor for detecting a rotor blade (430) comprising an electrical oscillator arranged to generate an oscillating signal. An antenna (300) includes a coil (100) having one or two winding layers coupled to the electrical oscillator. The antenna (300) may instead or as well include a …

Abstract:

Scanning tunnelling microscope (STM) comprising a first tip (10) for receiving a spin-polarised tunnelling current from a sample (50). Spin injector (20) is provided for injecting a spin-polarised current into the sample (50) and placeable in proximity with the sample (50).

Abstract:

La0.7Sr0.3MnO3 polycrystalline manganite thin films were grown on silicon (Si) substrates covered by SiOx amorphous native oxide. Curie temperatures of about 325 K were achieved for 70-nm-thick films. Strong room temperature XMCD signal was detected indicating high spin polarization at the surface. Cross-sectional TEM images show sharp interface between SiOx and manganite without signature of chemical reaction at the interface. Unusual sharp splitting of the manganite film was observed: on the top of a transition layer characterized by low crystalline order, a magnetically robust layer is formed. © 2007 Elsevier B.V. All rights reserved.