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Mater Sci Nanotechnol 2017
Volume 1 Issue 3
Magnetic Materials 2017
Page 84
October 09-10, 2017 London, UK
International Conference on
Probingtheelectronicandmagneticpropertiesof
magnetic oxides using resonant photoemission
study
R J Choudhary
UGC DAE Consortium for Scientific Research, India
T
he electrical and magnetic properties of any transition
metal oxide are related to its electronic structure.
Resonant photoemission spectroscopy (RPES) is a novel
technique to understand the valence band structure of any
transition metal based oxide material. In the present talk, I
shall discuss the results of different classes of magnetic oxide
materials. These materials are grown in thin film form using
pulsed laser deposition. X-ray photoelectron spectroscopy,
and RPES measurements have been performed at AIPES
beamline at Indus-1, RRCAT, Indore. For over a decade,
TM doped semiconducting oxides based dilute magnetic
semiconductors (DMS) have attracted a huge attention of
condensed matter community owing to its prospects in
spintronic applications. To better understand the effect
of TM doping or presence of defects on the electrical and
magnetic properties, it is crucial to realize modification in the
host semiconducting oxide’s electronic properties. We have
investigated the electronic and magnetic properties of the
pulsed laser deposited epitaxial thin films of Fe doped (4 at.
%) and undoped anatase TiO2-d by resonant photoemission,
resistivity, magnetization measurements and ab-initio band
structure calculations. Our study reveals the formation of
local magnetic moment and finite density of states at the Fermi
level indicating its metallic (degenerate semiconducting)
behaviour in both the films, leading to magnetic ordering
at room temperature and a Kondo minimum in resistivity
behaviour. Present work suggests that there is a competition
between magnetic ordering mechanism by JRKKY and
moment screening mechanism by JKondo. In the light of this
result the role of carrier density is also discussed in achieving
the magnetic ordering in DMS materials either by defect
engineering or by transition metal doping.
ram@csr.res.inMaterials Science and Nanotechnology