http://www2.physics.colostate.edu/groups/WuGroup/publications/MMM_2009_Recent%20advances%20in%20processing%20and%20applications%20of%20microwave%20ferrites.pdf

Recent advances in processing and applications of microwave ferrites

Microwave ferrites are ubiquitous in systems that send, receive, and manipulate electromagnetic signals across very high frequency to quasi-optical frequency bands. In this paper, modern microwave ferrites are reviewed including spinel, garnet, and hexaferrite systems as thin and thick films, powders and compacts, and metamaterials. Their fundamental properties and utility are examined in the context of high frequency applications ranging from the VHF to millimeter-wave bands. Perspective and outlook of advances in theory, processing, and devices occurring in the science and engineering communities since the year 2000 are presented and discussed.

Modern Microwave Ferrites

We review the recent developments in the electric field control of magnetism in multiferroic heterostructures, which consist of heterogeneous materials systems where a magnetoelectric coupling is engineered between magnetic and ferroelectric components. The magnetoelectric coupling in these composite systems is interfacial in origin, and can arise from elastic strain, charge, and exchange bias interactions, with different characteristic responses and functionalities. Moreover, charge transport phenomena in multiferroic heterostructures, where both magnetic and ferroelectric order parameters are used to control charge transport, suggest new possibilities to control the conduction paths of the electron spin, with potential for device applications.

https://iopscience.iop.org/article/10.1088/0953-8984/24/33/333201/pdf

Electric field control of magnetism in multiferroic heterostructures

Journal of Magnetism and Magnetic Materials. Volumes 198-199, 1 June 1999,

This review aims to summarise the progress in some materials and structures for electromagnetic applications, such as microwave absorption, electric shielding and antenna designs, which have been developed in recent years. Composites with spherical powders for microwave absorption focus mainly on those based on ferrites (especially hexagonal), carbonyl iron and related alloys and various newly emerged nanosized materials. Composites with long conductive fibres as fillers will be summarised, with speical attentions to prediction, measurment and evaluation of their performances. Metamaterials include structures for microwave absorbing applications, tunable materials or structures with reflection or transmission coefficients that are tunable by external magnetic or electric fields, and specially designed structures for microwave absorbing applications, with thickness much smaller than that of conventional composite materials and performances that can be optimised by the physical properties of substra...

Recent progress in some composite materials and structures for specific electromagnetic applications

Tunable negative index metamaterial using yttrium iron garnet

Recent Advances in Processing and Applications of Microwave Ferrites

Magnetic fringe fields emanating from a multiferroic heterostructure composite of Terfenol-D and lead magnesium niobate-lead titanate were utilized to actively tune a meander line microstrip ferrite phase shifter operating above ferrimagnetic resonance at C-band. Differential phase shifts of 65° were measured when tuned with an applied voltage to the multiferroic heterostructure. This demonstration of magnetoelectric field generation provides an alternative approach to tuning broadband planar microwave magnetic devices where neither strain nor direct electromagnetic coupling is experienced between device and multiferroic transducer.

https://repository.library.northeastern.edu/files/neu:330709/fulltext.pdf

Multiferroic heterostructure fringe field tuning of meander line microstrip ferrite phase shifter

A tunable compact phase shifter utilising negative refractive index metamaterial is demonstrated. The negative index metamaterial is composed of a periodic copper wire pattern sandwiched between two slabs of high quality yttrium iron garnet films. Near ferrimagnetic resonance, a phase shift tuning of 160°/kOe is achieved at 24 GHz. The insertion loss varies from 4 to 7 dB for a 1 cm-long composite.

Peng He

Papers

Recent advances in processing and applications of microwave ferrites

Tunable negative index metamaterial using yttrium iron garnet

Recent Advances in Processing and Applications of Microwave Ferrites

Multiferroic heterostructure fringe field tuning of meander line microstrip ferrite phase shifter

Tunable negative refractive index metamaterial phase shifter