Magnetic storage device using reentrant hysteresis materials

Claim 1

IN COMBINATION, A WIRE OF MAGNETIC MATERIAL HAVING A PRINCIPAL, SQUARELOOP, HYSTERESIS CHARACTERISTIC DEFINING TWO STABLE CONDITIONS OF MAGNETIC REMANENCE AND HAVING A FIRST THRESHOLD FIELD REQUIRED TO INITIATE SWITCHING BETWEEN SAID STABLE CONDITIONS, SAID CHARACTERISTIC HAVING REENTRANT SWITCHING PORTIONS WITH A SECOND AND SMALLER THRESHOLD FIELD REQUIRED TO MAINTAIN A SWITCHING OPERATION, A LEAD WRAPPED AROUND A LENGTH OF SAID WIRE, MEANS APPLYING CURRENT TO SAID LEAD FOR GENERATING IN SAID WIRE LENGTH A FIELD WHICH IS AT LEAST EQUAL TO SAID SECOND THRESHOLD FIELD BUT LESS THAN SAID FIRST THRESHOLD FIELD, A CIRCUIT ELECTROMAGNETICALLY ENGAGING A SMALL SEGMENT OF SAID WIRE LENGTH, AND MEANS APPLYING TO SAID CIRCUIT A PULSE FOR GENERATING A FIELD IN SAID SEGMENT WHICH IS AT LEAST EQUAL TO SAID FIRST FIELD, THE LENGTH OF SAID SEGMENT BEING PROPORTIONED IN RELATION TO THE MAGNITUDE OF SAID PULSE SO THAT A MAGNETIC DOMAIN NUCLEATED BY THE FIELD OF SAID PULSE IS UNSTABLE UNLESS EXPANDED BY THE FIELD OF SAID CURRENT.