jap banner
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

SECTION LISTING

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

1 Mar 1969

Volume 40, Issue 3, pp. 915-1604

Return to All Sections
back to top
RSS Feeds
back to top MAGNETISM AND TECHNOLOGY

Role of Magnetism in Technology

I. S. Jacobs

J. Appl. Phys. 40, 917 (1969); http://dx.doi.org/10.1063/1.1657796 (12 pages) | Cited 7 times

Online Publication Date: 17 November 2003

Full Text: | Download PDF

Show Abstract
Magnetism applications permeate our whole modern society in its basics of electric power, communications, and information storage. Although the general public is mostly unaware of its role, magnetism has an economic impact of over 1% of the Gross National Product. The annual direct magnetic materials market is currently estimated at 650 million dollars, with dollar leadership shared by electrical steels and recording tape, followed by soft ferrites, magnetic disk packs and drums, permanent magnets, and nickel‐iron alloys. The magnetism market is also described with reference to the role of research leading to quality improvement and to a growing list of new applications. It is estimated that the cost of basic and applied research (U.S.) is about 5% of the direct magnetics market. The world output of publications on magnetics has increased sixfold over the past decade after a plateau during the 1950's. During this same period magnetism has become more popular relative to a total science publication base and its scope has broadened in research, in discovery, and in application.

Magnetics in Memory

A. V. Pohm

J. Appl. Phys. 40, 928 (1969); http://dx.doi.org/10.1063/1.1657797 (1 page)

Online Publication Date: 17 November 2003

Full Text: | Download PDF

Show Abstract
Magnetic memory cells meet the essential logical and economic requirements1,2 of a memory cell and presently play a dominant role in electronically and mechanically accessed computer memories.3,4 Electronically addressed magnetic memories typically are arranged in 3D, 2D, or 2☒D organizations.5–9 Progress in electronically addressed magnetic memories has resulted from a number of basic discoveries and developments in the threshold and switching properties of ferrite cores,10–12 planar thin films,13–15 and plated wires.16 As recently summarized,17,18 mechanically accessed memories such as tapes, drums, disks and data cells have had continual improvements in magnetic materials and in cell density. Present magnetic cells typically do not approach the limits set by thermal noise,19,9 and, as a consequence, a substantial increase in density is possible. The number of magnetic memory cells produced each year is increasing by more than 30% per year3 and continued growth can be anticipated.

Magnetism in Microwave Devices

G. P. Ridrigue

J. Appl. Phys. 40, 929 (1969); http://dx.doi.org/10.1063/1.1657798 (9 pages) | Cited 1 time

Online Publication Date: 17 November 2003

Full Text: | Download PDF

Show Abstract
The functions of ferrite components in advanced microwave systems are briefly outlined, and the principal requirements described. The successful development of these sophisticated devices is the cumulative result of contributions from many areas of basic research and technology. As an example of the dependence of device performance on diverse efforts, the status and evolution of ferromagnetic digital phasers are reviewed. In this instance, materials research, ceramic technology, methods of numerical analysis, and the understanding of basic damping mechanisms have all contributed to the realization of practical devices. The application of ferrite devices to microwave integrated circuits is also outlined and some recent experimental results given. Other new trends in the field of microwave ferrite devices are briefly mentioned, as are areas most in need of further research.

Potentially Useful Properties of Magnetic Materials

H. S. Jarrett

J. Appl. Phys. 40, 938 (1969); http://dx.doi.org/10.1063/1.1657799 (7 pages) | Cited 3 times

Online Publication Date: 17 November 2003

Full Text: | Download PDF

Show Abstract
Magnetism has played a vital role in the development of basic concepts of solid‐state physics. Early research in magnetism was concerned largely with the reaction of the magnetization on external applied static and electro‐magnetic fields. Indeed, technological developments in magnetism have utilized such behavior highly successfully. Today's trend in basic magnetics research emphasizes the interrelation of magnetism with other physical properties of solids. For example, magneto‐electronic, ‐optical, and ‐electric properties of materials, the magnitude of the interaction, and how external fields coupled to the magnetization influence other properties is the subject of many of the basic papers in this Conference. This paper reviews current magnetics research with emphasis on the experimental observations. These effects provide a wealth of new material on which to base future technological applications.
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close