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Quantum and Ballistic Nanodevices

Shorubalko, Ivan LU (2003)
Abstract
In this thesis, electron transport in quantum and ballistic devices was studied. The devices studied here were quantum wires, planar quantum dots, ballistic rectifiers, artificial functional materials, and three-terminal ballistic junctions. The possible application of such devices in the future nanoelectronics was also investigated.



In an electron waveguide, with an abrupt change in the geometry at the entrance and the exit, conductance oscillations, superimposed on conventional conductance plateaus, were observed. These oscillations were attributed to formation of longitudinal, resonant electron states in the waveguide, in analogy with optical Fabry-Perot effects.



The Coulomb charging effects and the... (More)
In this thesis, electron transport in quantum and ballistic devices was studied. The devices studied here were quantum wires, planar quantum dots, ballistic rectifiers, artificial functional materials, and three-terminal ballistic junctions. The possible application of such devices in the future nanoelectronics was also investigated.



In an electron waveguide, with an abrupt change in the geometry at the entrance and the exit, conductance oscillations, superimposed on conventional conductance plateaus, were observed. These oscillations were attributed to formation of longitudinal, resonant electron states in the waveguide, in analogy with optical Fabry-Perot effects.



The Coulomb charging effects and the resonant tunneling through the lowest quantized energy level of the heterostructurally defined, planar quantum dots were studied.



The ballistic rectifiers were fabricated to be small enough to show ballistic effects even at room temperature. In analogy to the ballistic rectifiers, the artificial functional nanomaterial was proposed and fabricated. The ballistic rectifiers as well as the artificial nanomaterials showed functionality at room temperature and at frequencies up to at least 50 GHz. Quantum effects in the transport behavior of the nano-scale ballistic rectifiers and the artificial materials were found to be dominant at low temperatures.



Nonlinear electrical properties of three-terminal ballistic junctions were investigated. Three-terminal ballistic junctions were found to show nonlinear current-voltage, and voltage-voltage characteristics tunable by voltages applied either to one of the branches of the junction or to an external capacitively-coupled gate. These nonlinear electrical properties are observable even at room temperature and are therefore interesting from an application point of view. Integrated devices, such as the frequency multipliers based on a three-terminal ballistic junction were proposed and demonstrated. The fabricated frequency multipliers showed frequency doubling and gain at room temperature. (Less)
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author
opponent
  • Professor Aoyagi, Yoshinobu, Japan
organization
publishing date
type
Thesis
publication status
published
subject
keywords
III-V semiconductors, low-dimensional structures, nanostructures, ballistic rectifiers, three-terminal ballistic junctions, quantum wires, planar quantum dots, logic gates, harmonic generation, InP, GaInAs, nanoelectronics, Fysik, Physics, nonlinear transport, electron transport, quantum nanodevices, ballistic nanodevices, Fysicumarkivet A:2003:Shorubalko
pages
106 pages
publisher
Division of Solid State Physics, Lund University, Box 118, SE-221 00 Lund, Sweden,
defense location
Dept of Physics, room B, Lund Institute of Technology
defense date
2003-06-06 13:15
ISBN
91-628-5707-X
language
English
LU publication?
yes
id
3ebbd3c8-af53-4c99-a578-e5c59bf198db (old id 465971)
date added to LUP
2007-10-01 09:45:20
date last changed
2016-09-19 08:45:11
@phdthesis{3ebbd3c8-af53-4c99-a578-e5c59bf198db,
  abstract     = {In this thesis, electron transport in quantum and ballistic devices was studied. The devices studied here were quantum wires, planar quantum dots, ballistic rectifiers, artificial functional materials, and three-terminal ballistic junctions. The possible application of such devices in the future nanoelectronics was also investigated.<br/><br>
<br/><br>
In an electron waveguide, with an abrupt change in the geometry at the entrance and the exit, conductance oscillations, superimposed on conventional conductance plateaus, were observed. These oscillations were attributed to formation of longitudinal, resonant electron states in the waveguide, in analogy with optical Fabry-Perot effects.<br/><br>
<br/><br>
The Coulomb charging effects and the resonant tunneling through the lowest quantized energy level of the heterostructurally defined, planar quantum dots were studied.<br/><br>
<br/><br>
The ballistic rectifiers were fabricated to be small enough to show ballistic effects even at room temperature. In analogy to the ballistic rectifiers, the artificial functional nanomaterial was proposed and fabricated. The ballistic rectifiers as well as the artificial nanomaterials showed functionality at room temperature and at frequencies up to at least 50 GHz. Quantum effects in the transport behavior of the nano-scale ballistic rectifiers and the artificial materials were found to be dominant at low temperatures.<br/><br>
<br/><br>
Nonlinear electrical properties of three-terminal ballistic junctions were investigated. Three-terminal ballistic junctions were found to show nonlinear current-voltage, and voltage-voltage characteristics tunable by voltages applied either to one of the branches of the junction or to an external capacitively-coupled gate. These nonlinear electrical properties are observable even at room temperature and are therefore interesting from an application point of view. Integrated devices, such as the frequency multipliers based on a three-terminal ballistic junction were proposed and demonstrated. The fabricated frequency multipliers showed frequency doubling and gain at room temperature.},
  author       = {Shorubalko, Ivan},
  isbn         = {91-628-5707-X},
  keyword      = {III-V semiconductors,low-dimensional structures,nanostructures,ballistic rectifiers,three-terminal ballistic junctions,quantum wires,planar quantum dots,logic gates,harmonic generation,InP,GaInAs,nanoelectronics,Fysik,Physics,nonlinear transport,electron transport,quantum nanodevices,ballistic nanodevices,Fysicumarkivet A:2003:Shorubalko},
  language     = {eng},
  pages        = {106},
  publisher    = {Division of Solid State Physics, Lund University, Box 118, SE-221 00 Lund, Sweden,},
  school       = {Lund University},
  title        = {Quantum and Ballistic Nanodevices},
  year         = {2003},
}