Patent · US Expired

Controllable state conversions for S=1 bubble domains

US4068220A · kind A · utility

3Cited by
1References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1976
Grant dateJan 10, 1978
Priority date
Expiry dateJun 17, 1996

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C19/0858
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A technique for controllably providing state conversions between bubble domains having a common winding number S is described. In particular, controlled conversions between bubble domains having winding number S=1 is achieved by the application of spatially invariant, homogeneous magnetic fields. For the conversion of .sigma. bubbles (having two vertical Bloch lines) to .chi. bubbles (having no vertical Bloch lines), an in-plane field is not required and only a time varying perpendicular z-field is used. For conversion of a .chi..sub.+ bubble to a .chi..sub.- bubble, and vice versa, a time varying field pulse is applied, there being no requirement for an in-plane magnetic field. However, for the conversion of .chi. bubbles to .sigma. bubbles, an in-plane field is used simultaneously with a time varying z-field. For all controlled conversions, the applied magnetic fields do not have spatial gradients. The magnitudes of the applied magnetic fields and the rise and fall times of the z field are controlled within certain ranges in order to have controlled conversion of one state to another.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.