2,100 research outputs found
Planar Heterostructure Graphene -- Narrow-Gap Semiconductor -- Graphene
We investigate a planar heterostructure composed of two graphene films
separated by a narrow-gap semiconductor ribbon. We show that there is no the
Klein paradox when the Dirac points of the Brillouin zone of graphene are in a
band gap of a narrow-gap semiconductor. There is the energy range depending on
an angle of incidence, in which the above-barrier damped solution exists.
Therefore, this heterostructure is a "filter" transmitting particles in a
certain range of angles of incidence upon a potential barrier. We discuss the
possibility of an application of this heterostructure as a "switch".Comment: 9 pages, 2 figure
The main directions for pharmacological correction (combinations of drugs for general anesthesia) of neurological and cognitive disorders in patients with neoplasms of the central nervous system
The aim of the study was to develop a goal-oriented combination of drugs for general anesthesia, based on a retrospective assessment of the baseline level of neurological and cognitive disorders in adults and children at the stage of preparation for surgery for neoplasms of the central nervous system (sub- and supratentorial neoplasms - SubTNN and SupraTNN), and a prospective evaluation of complications in the postoperative perio
Interface states in junctions of two semiconductors with intersecting dispersion curves
A novel type of shallow interface state in junctions of two semiconductors
without band inversion is identified within the envelope function
approximation, using the two-band model. It occurs in abrupt junctions when the
interband velocity matrix elements of the two semiconductors differ and the
bulk dispersion curves intersect. The in-plane dispersion of the interface
state is found to be confined to a finite range of momenta centered around the
point of intersection. These states turn out to exist also in graded junctions,
with essentially the same properties as in the abrupt case.Comment: 1 figur
Boundary States in Graphene Heterojunctions
A new type of states in graphene-based planar heterojunctions has been
studied in the envelope wave function approximation. The condition for the
formation of these states is the intersection between the dispersion curves of
graphene and its gap modification. This type of states can also occur in smooth
graphene-based heterojunctions.Comment: 5 pages, 3 figure
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