The principle of nanotechnology is the manipulatio

The principle of nanotechnology is the manipulation of
the matter at the nanoscale in order to take advantage of
the different physical properties of materials via size and
shape fine tuning. Amongst the more relevant
nanoscience advancements an important place is taken by
quantum confinement effects that take place in three
dimensional semiconductor nanostructures. Because of
them, these quantum nanostructures (QN) can be
considered as artificial atoms and like the natural atoms
show a discrete spectrum of energy levels [1]. More than
natural atoms, QNs electronic properties can be finely
tuned, on demand, adjusting structural parameters, such
as size, composition and morphology. The latter
parameter is the most relevant for the control of the QN
electronic properties, as tiny variations in morphology
can cause dramatic changes on the electronic properties
[2]. One of the most pursued method for the fabrication of
QNs is the molecular beam epitaxy (MBE) growth of
lattice‐mismatched III‐V semiconductor materials via the
Stranki‐Krastanov (SK) mode [3]. This technique exploits the self‐assembly of pyramidal‐like QNs, driven by the
relaxation of strain accumulated in the epilayer. Despite
the high success of the technique, which led to
fundamental physical understandings and to a variety of
applications [3‐5], the available design degrees of
freedom remain limited. The precise engineering of size
and shape of QNs via SK self‐assembly remains
problematic [6], thus limiting the possibilities of a real on
demand design of the electronic properties. It is worth
mentioning that the possibility to control QN shape
allows to access fundamental quantum design parameters
that include geometrical quantum phase [7], spin‐spin
interaction [8] and quantum state couplings [9].

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The
average size, which is estimated from individual spherical
nanocrystals, is ~3.1 nm, 3.6 nm and 3.4 nm for SnO2,
Sn0.95Fe0.05O2 and Sn0.95Ni0.05O2 samples, respectively. Thus
calculated particle sizes are in very good agreement to
those calculated from XRD data. Fig. 3 (a‐e) shows the
EDAX spectra, collected from the average scanned area, of
un‐doped SnO2, Sn0.97Fe0.03O2, Sn0.95Fe0.05O2, Sn0.97Ni0.03O2 and
Sn0.95Ni0.05O2 samples, respectively. The self generated
elemental composition (wt. %) details are also presented in
the Fig. 3. It is clear from the Fig. 3 that Sn, and O are only
the main elemental species in pure SnO2 sample while,
additionally, Fe and Ni peaks were observed in Fe and Ni
doped samples.

Magnetic Properties of Fe and Ni
Doped SnO2 Nanoparticles
Regular paper
Aditya Sharma1,*, Mayora Varshney1, Shalendra Kumar2, K. D. Verma1 and Ravi Kumar3