Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Impurity induced spin gap asymmetry in nanoscale graphene   We propose a unique way to control both bandgap and the magnetic properties
of nanoscale graphene, which might prove highly beneficial for application in
nanoelectronic and spintronic devices. We have shown that chemical doping by
nitrogen along a single zigzag edge breaks the sublattice symmetry of graphene.
This leads to the opening of a gap and a shift of the molecular orbitals
localized on the doped edge in such a way that the spin gap asymmetry, which
can lead to half-metallicity under certain conditions, is obtained. The
spin-selective behavior of graphene and tunable spin gaps help us to obtain
semiconductor diode-like current-voltage characteristics, where the current
flowing in one direction is preferred over the other. The doping in the middle
of the graphene layer results in an impurity level between the HOMO and LUMO
orbitals of pure graphene (again, much like in semiconductor systems) localized
on the zigzag edges thus decreasing the bandgap and adding unpaired electrons,
and this can also be used to control graphene conductivity.

15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio