Method for making large area stable domains
US4563236A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1981 |
| Grant date | Jan 7, 1986 |
| Priority date | — |
| Expiry date | Nov 13, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F41/14
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for producing a large area of single domain magnetic bistability is shown including the steps of selecting the properties of films of magnetic materials such that the saturation field (H.sub.s) that is less than the value of the anisotropy field (H.sub.k) reduced by the value of a demagnetization factor (4.pi.) times the magnetization value (M.sub.s) as stated in the equation: EQU H.sub.s <H.sub.k -4.pi.M.sub.s. Isolated areas are created in these films by means which do not introduce changes in the magnetic properties, such as stress anisotropy effects. Large area stable domains exist in material whose measured magnetic properties meet this relationship independent of temperature and without a requirement for a magnetic bias.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.