Discovery: Magnetic
properties of cobalt films can be optimized through nanoscale
structuring and thermal annealing.
Approach
& Results:
Periodically organized cobalt structures were fabricated by self-assembly and
electrochemical deposition. Magnetic properties of these structures were
revealed by magneto-optical Kerr effect studies and a magnetic pinning-site
model.
Significance:
This nanoscale fabrication approach is the
first step towards 3D magnonic
crystals, a new type of magnetic metamaterial with potential to control
spin-wave propagation and spin density of states.
Scanning
electron micrograph of a ferromagnetic, ordered cobalt nanostructure.
Magnetic
hysteresis of nanostructured cobalt without heat treatment (a),
annealed
at 350 ºC (b), 440 ºC (c), and 500 ºC (d).
