Write circuit using enhanced propagation pulses for lateral displacement coding of patterns of single-wall magnetic domains

Claim 2

A single-wall magnetic domain apparatus, comprising: a layer of material in which single-wall magnetic domains can be moved; means for defining a domain propagation channel in said layer; means for defining a sequence of consecutive domain positions along said channel, said channel being characterized by a first stable domain location on one side of said channel at each of said positions, and a second stable domain location on the other side of said channel at each of said positions, said locations at each of said positions being substantially laterally displaced with respect to the direction of domain propagation in said channel; and means for providing a sequence of consecutively offset magnetic fields for moving a domain along said Positions in response to a sequence of first propagation pulses of a predetermined amplitude and second propagation pulses of a different amplitude, such that domain movement between consecutive positions in said channel is constrained to movement between locations on the same side of said channel in response to said first pulses and to movement between locations on opposite sides of said channel at at least one of said positions in response to said second pulses.

Claim 3

The single-wall magnetic domain apparatus in accordance with claim 1, in which said means for defining said sequence of consecutive domain positions comprises means for generating at a selected position a force sufficient to laterally displace a domain at such position from one of said locations to the other in response to one of said second propagation pulses, said second pulses each having a larger amplitude with respect to said predetermined amplitude of said first propagation pulses.

Claim 4

The single-wall magnetic domain apparatus in accordance with claim 2, in which said generating means comprises a propagation conductor pattern that repeatedly crosses said channel, the lateral dimensions of said conductor pattern at said selected position being sufficiently reduced with respect to the lateral dimensions of said conductor pattern at others of said positions to provide said displacement force in response to one of said second propagation pulses.

Claim 5

The single-wall magnetic domain apparatus in accordance with claim 3 in which the lateral dimensions of said conductor pattern at said positions other than said selected position are sufficient to preclude lateral displacement of domains at such positions in response to either said first pulses or said second pulses.

Claim 6

The single-wall magnetic domain apparatus in accordance with claim 4 in which said lateral dimensions of said conductor pattern at said selected position are reduced on a predetermined side of said channel so that displacement of a domain to said predetermined side at said selected position occurs in response to one of said second propagation pulses having a predetermined corresponding polarity.

Claim 7

The single-wall magnetic domain apparatus in accordance with claim 2 in which said generating means comprises a conductor pattern having a substantially serpentine geometry suitable for generating a pattern of attracting and repelling magnetic fields along said channel, for sequentially propagating domains between said positions in said channel in response to said first pulses having alternating polarity; said serpentine geometry of said conductor pattern at said selected position having reduced dimensions, with respect to corresponding dimensions of said serpentine geometry at others of said positions, in a direction at substantially right angles with respect to the direction of domain propagation along said channel; said channel being of a suitable material and geometry to define first and second sides thereof and to constrain domains to propagate along either of said sides without switching sides in response to said first pulses; and said reduced dimensions of said serpentine geometry at said selected position being sufficiently reduced to effect the binary ''''write'''' function by displacing a domain propagating into such position from said first side to said second side of such position in response to one of said second pulses having a predetermined polarity.

Claim 8

The single-wall magnetic domain apparatus in accordance with claim 6 in which said channel comprises a magnetically soft rail with a predetermined thickness and a lateral width less than the diameter of a domain in said layer of material.

Claim 9

The single-wall magnetic domain apparatus in accordance with claim 6 in which said channel comprises a serrated groove of a predetermined width and depth in said layer of material.

Claim 10

The single-wall magnetic domain apparatus in accordance with claim 3 in which: said conductor pattern having reduced lateral dimensions in a first lateral direction at a first one of said positions whereby a domain in said first location at said first position moves to said second location of said first position in response to one of said second propagation pulses when such pulse is of a positive polarity; and said conductor pattern having reduced lateral dimensions in a second lateral direction at a second one of said positions whereby a domain in said second location at said second position moves to said first location of said second position in response to one of said second propagation pulses when such pulse is of a negative polarity.

Claim 11

In combination: a layer of material in which single-wall magnetic domains are movable; means for defining a domain propagation channel in said layer; a conductor pattern having first and second geometries defining domain positions along said channel, said first and second geometries comprising patterns that cross said channel and the lateral dimensions of said second geometry being reduced with respect to the lateral dimensions of said first geometry; and means for providing first and second pulses to said conductor pattern, such that a domain moves along one side of said channel in response to one of said first pulses and moves from one side to the other side of said channel at a position defined by said second geometry in response to one of said second pulses.

Claim 12

In combination: a layer of material in which single-wall magnetic domains are movable; means for defining a domain propagation channel in said layer; a conductor pattern having first and second geometries defining domain positions along said channel, said first and second geometries comprising patterns that cross said channel and the lateral dimensions of said second geometry being reduced with respect to the lateral dimensions of said first geometry; and means for providing first and second pulses to said conductor pattern, such that a domain moves along one side of said channel in response to one of said first pulses and moves from one side to the other side of said channel at a position defined by said second geometry in response to one of said second pulses.