Uhf Ferromagnetic Phase Shifters (200-400 Mc).

Uhf Ferromagnetic Phase Shifters (200-400 Mc).
Author: WILLIAM D. FITZGERALD
Publisher:
Total Pages: 1
Release: 1961
Genre:
ISBN:

UHF ferrite phase shifters are discussed which are unusually compact and require low drive fields. These devices use a dual-mode network with non-linear phase properties. The non-linear phase-multiplier property of this network enables the design and construction of very compact devices. Their operation is based on domainwall resonance. The material chosen has an internal magnetic field large enough for operation above ferromagnetic resonance, so operation is in the low loss region even for zero, or small, applied control fields. The closed path toroidal geometry implies an efficient magnetic circuit and also contributes to the low field requirements. Two ferrite phase shifters were constructed using the dual-mode network. The first, designed for narrow band operation in the 200 to 350 mc range, is composed of eight dual-mode sections arranged to form a concentric square crosssection. The side dimension of this square is 2-1/8 inches; the length of the phase shifter is 3-1/8 inches. The second device, designed to cover the broader band from 225 to 400 mc, is composed of six dual-mode sections set in a concentric triangular cross-section. This triangle is approximately 2-1/2 inches on a side and the strip-line in this case is approximately 2-1/3 inches long. The first device requires 100 oersteds drive field for 360 degrees differential phase shift while the second device requires 130 oersteds for the same phase shift. (Author).

UHF FERROELECTRIC PHASE SHIFTER RESEARCH.

UHF FERROELECTRIC PHASE SHIFTER RESEARCH.
Author: M. COHN
Publisher:
Total Pages: 1
Release: 1962
Genre:
ISBN:

The analysis, construction, and performance of compact surface wave ferroelectric phase shifters suitable for operation in the 100 to 1000 mc frequency range are described. Although this ferroelectric loaded parallel plane structure is a very low impedance structure, a satisfactory terminal impedance matching technique has been devised, Kilovolt level voltages are needed; but since the current required to maintain or rapidly shift phase is low, the over-all control power requirements are at least an order of magnitude less than those for comparable ferrite phase shifters. One of these room temperature operable phase shifters provided 348 degrees of phase shift and had an insertion loss which varied from 3.7 to 2.2 db at 207 mc and over a zero to 4000 volt range of applied dc control voltage. (Author).

Handbook of Spintronics

Handbook of Spintronics
Author: Yongbing Xu
Publisher: Springer
Total Pages: 0
Release: 2015-10-14
Genre: Science
ISBN: 9789400768918

Over two volumes and 1500 pages, the Handbook of Spintronics will cover all aspects of spintronics science and technology, including fundamental physics, materials properties and processing, established and emerging device technology and applications. Comprising 60 chapters from a large international team of leading researchers across academia and industry, the Handbook provides readers with an up-to-date and comprehensive review of this dynamic field of research. The opening chapters focus on the fundamental physical principles of spintronics in metals and semiconductors, including an introduction to spin quantum computing. Materials systems are then considered, with sections on metallic thin films and multilayers, magnetic tunnelling structures, hybrids, magnetic semiconductors and molecular spintronic materials. A separate section reviews the various characterisation methods appropriate to spintronics materials, including STM, spin-polarised photoemission, x-ray diffraction techniques and spin-polarised SEM. The third part of the Handbook contains chapters on the state of the art in device technology and applications, including spin valves, GMR and MTJ devices, MRAM technology, spin transistors and spin logic devices, spin torque devices, spin pumping and spin dynamics and other topics such as spin caloritronics. Each chapter considers the challenges faced by researchers in that area and contains some indications of the direction that future work in the field is likely to take. This reference work will be an essential and long-standing resource for the spintronics community.