[PDF]
http://dx.doi.org/10.3952/lithjphys.52206
Open access article / Atviros prieigos straipsnis
Lith. J. Phys. 52, 126–141 (2012)
QUASI-BOUND
STATES
OF DIRAC ELECTRONS IN ELECTRIC AND MAGNETIC QUANTUM DOTS
A. Matulis
Semiconductor Physics Institute, Center for Physical Sciences and
Technology, A. Goštauto 11, LT-01108 Vilnius, Lithuania
E-mail: amatulis@takas.lt
Received 19 March 2012; accepted 7 June 2012
The problem of quasi-bound states
for
ultra-relativistic Dirac electrons and holes in electric and
magnetic
quantum dots in graphene is discussed. It is shown that these
states
with a rather long lifetime appear in an electric quantum dot in
the
case of a large orbital momentum, and in a magnetic quantum dot if
its
dimensions exceed the Larmor radius of the electron. The
quasibound
state properties are analysed by using the local density of states
technique the application of which is demonstrated by a simple
one-dimensional model of the decaying state. In addition, the
analogy
between two-dimensional graphene and onedimensional polymers is
discussed, which helps in understanding and interpreting the
sophisticated features of the electron spectrum.
Keywords: graphene, Dirac
electrons, quantum dots, quasi-bound states
PACS: 73.63.Kv, 73.43.Cd,
81.05.Uw, 03.65.-w, 73.21.La
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