Current-Controlled Magnetic Domain-Wall Nanowire Shift Register
Masamitsu Hayashi,
Luc Thomas,
Rai Moriya,
Charles Rettner,
Stuart S. P. Parkin*
The controlled motion of a series of domain walls along magnetic
nanowires using spin-polarized current pulses is the essential
ingredient of the proposed magnetic racetrack memory, a new
class of potential non-volatile storage-class memories. Using
permalloy nanowires, we achieved the successive creation, motion,
and detection of domain walls by using sequences of properly
timed, nanosecond-long, spin-polarized current pulses. The cycle
time for the writing and shifting of the domain walls was a
few tens of nanoseconds. Our results illustrate the basic concept
of a magnetic shift register that relies on the phenomenon of
spin-momentum transfer to move series of closely spaced domain
walls.
* To whom correspondence should be addressed. E-mail: parkin{at}almaden.ibm.com
