10-11-2012, 02:36 PM
Magnetic Information in the Light Diffracted by Submicronscale
Periodic Magnetic Arrays
Magnetic Information in the Light Diffracted by Submicron.pdf (Size: 252.05 KB / Downloads: 23)
INTRODUCTION
The precise control of microstructure offered by
modern photolithography [1] now makes it possible
to produce periodic arrays of sub-micron structures in
metallic and superconducting films. This new control
over the sizes, periods and symmetry of the
microstructures enables not only the fabrication of
new systems of potential technological interest, but
also systems in which fundamental properties of
mesoscopic matter can be investigated. The
correlation of the magnetic properties of arrays of
patterned structures to the size and the shape of the
single unit, as well as to the array spacing, is a central
issue which is still not well understood. A key issue
in fundamental physics and data storage technology
is to understand and control the magnetic switching
of small magnetic elements. Much of the drive for
these investigations is the hope that understanding
magnetism at these length scales will enable
advanced spintronic devices to be realized. In spite of
the considerable effort so far devoted to investigate
these problems, there are still many unanswered
questions.
THEORY OF D-MOKE
In this section, we briefly summarize the
mathematical formalism which allows a quantitative
analysis of the D-MOKE loops.
The D-MOKE loops to be discussed in this work
were recorded in what is known as the ‘transverse
MOKE’ configuration; the applied field is
perpendicular to the plane that contains both the
direction of incident light and the surface normal.
Only the intensity of the reflected light is monitored
(i.e., no analyzer is used in the reflected beam).
D-MOKE FROM DOT ARRAYS
The D-MOKE technique has demonstrated its
ability to provide insights into the magnetization
structures developing during switching in a variety of
different cases: inside the elements of an array of
dots or rings [10-16] and around the holes in an array
of antidots [5-9].