Speaker
Mrs
LAILA OBIED
(brock university-physics department)
Description
The synthesis of Dilute magnetic semiconductors (DMS) has attracted great interest
because of the potential application of these materials in spintronics. DMS can be
fabricated by alloying semiconductors with magnetic transition metal elements (TM),
such as Mn. However, the concentration of TM needed to realize the ferromagnetic order
in a semiconductor is still hard to achieve because of the low solid solubility of TM in
semiconductors. Non-equilibrium methods, such as low temperature Molecular Beam
Epitaxy (MBE) and ion implantation, have been suggested to increase the solubility of
TM in a semiconductor host .
The aim of this work is the synthesis of Ge:Mn DMS and study the fundamental
origin of ferromagnetism in this system. Using ion implantation, a single crystal Ge wafer
was doped with magnetic Mn2+ ions at 77 K. A superconducting quantum interference
device (SQUID) was used to investigate the magnetic properties of three samples. Pure
Ge exhibited diamagnetic behaviour. The magnetic measurements of the amorphous
implanted sample showed a Curie paramagnetic behaviour at low temperature which
can be explained by the localized magnetic moments. However, The eld-dependent
magnetization of the implanted and annealed sample exhibits magnetic Hysteresis at 5K
and 200 K indicating the existence of some FM phases in the sample after annealing.
Author
Mrs
LAILA OBIED
(brock university-physics department)
Co-authors
Prof.
DAVID CRANDLES
(BROCK UNIVERSITY)
Prof.
Sjoerd Roorda
(UNIVERSITY OF MONTREAL)
