Browsing Theses  Department of Physics by Title
Now showing items 106125 of 225

Josephson effect in hybrid superconductornormal metal structures
(Bilkent University, 2000)The clean SNS junction, with a phase difference x across the normal metal barrier and without Fermi level mismatch between the components, is modeled by a step like pair potential. The quasiclassical equations are obtained ... 
Largescale semiempirical pseudopotential electronic structure of selfassembled ingaas quantum dots
(Bilkent University, 201809)The socalled second quantum revolution emerged at the beginning of the second millennium, opening up a path to realization of spinqubitbased quantum computing by means of controlling and protecting quantum coherent ... 
The left hand of electromagnetism : metamaterials
(Bilkent University, 2010)Metamaterials are artificial periodic structures whose electromagnetic response is solely dependent on the constituting unit cells. In the present thesis, we studied unit cell characteristics of metamaterials that has ... 
Light matter interaction in plexcitonic crystals and moiré cavities
(Bilkent University, 201501)Surface plasmon polaritons (SPPs) are quanta of electromagnetic excitations at the interface between metal and dielectric media. SPPs with an evanescent tail in the perpendicular direction, thus their properties are ... 
Light scattering from coreshell nanostructures : structural coloration
(Bilkent University, 2013)In this work, we produced kilometerlong semiconducting cylindrical nanostructures by using a toptobottom nanofabrication technique which was recently developed in our research group. Comparison of commonly used ... 
Logistic cellular automata
(Bilkent University, 201909)Cellular Automata (CA), initially formalized to investigate selfreproducing constructions, are among the most frequently used tools to model and understand complex systems. These computational frameworks are de ned in ... 
Long wavelength GaAs based hot electron photoemission detectors
(Bilkent University, 1999)The increasing rate of telecommunication alters both science and technology, and demands high performance components. Photo detectors are essential components of optoelectronic integrated circuits and fiber optic ... 
Low dimensional structures for optical and electrical applications
(Bilkent University, 2008)Low dimensional structures such as quantum dots have been particularly attractive because of their fundamental physical properties and their potential applications in various devices in integrated optics and microelectronics. ... 
Low loss optical waveguides and polarization splitters with oxidized AlxGa1xAs layers
(Bilkent University, 1998)Low propagation loss waveguides, operating at 1.55 fim optical wavelength, are fabricated utilizing oxidized AhGai_a;As layers. MBE grown multilayer semiconductor heterostructures are characterized before and after ... 
Lowtemperature thermodynamics of finite and discrete quartic quantum oscillator in one dimension
(Bilkent University, 1999)I.' this work we examined a quartic Hamiltonian using two different approaches. We first introduced a meanfield Gaussian approximation in order to handle this Hamiltonian analytically and observed that this approximation is ... 
Magnetism of transition metal nanowires
(Bilkent University, 2008)In this thesis we investigated structural, electronic and magnetic properties of 3d (light) transition metal (TM) atomic chains and Cr nanowires using firstprinciples pseudopotential plane wave calculations. Infinite ... 
Manipulation and control of collective behavior in active matter systems
(Bilkent University, 201611)Active matter systems consist of active constituents that transform energy into directed motion in a nonequilibrium setting. The interaction of active agents with each other and with their environment results in collective ... 
Manybody effects in selected twodimensional systems
(Bilkent University, 2009)In this thesis we study manybody effects in three distinct twodimensional systems. The two dimensional electron gas is a model system yielding to basic analytical and computational theoretical ideas of manybody physics ... 
Manybody interaction effects in quasionedimensional photoexcited electronhole systems
(Bilkent University, 1999)The work in this thesis concerns rnanybody interaction effects in a quasionedimensional electronhole plasma, which may be generated under intense photoexcitation in a semiconductor quantumwell wire. In particular, ... 
Manybody properties of onedimensional systems with contact interaction
(Bilkent University, 1999)The onedimensional electron systems are attracting a lot of interest because of theoretical and technological implications. These systems are usually fabricated on twodimensional electron systems by confining the ... 
Meanfield renormalization group theory of the tJ model
(Bilkent University, 2002)The quantum nature of the high temperature superconductivity models makes analytical approaches to these systems almost impossible to implement. In this thesis, a computational study of the one and two dimensional t − J ... 
Mechanical and electronic properties of metal chain nanowires
(Bilkent University, 2003)The fabrication of stable gold monoatomic chains suspended between two gold electrodes is one of the milestones in nanoscience and technology, since miniaturization of the electronic components is one of the great ... 
Metal coverage on singlewall carbon nanotubes : metal nanoring and nanotube formation
(Bilkent University, 2002)The carbon nanotubes are welcomed as the basis element for electronic and optoelectronic devices of nanometers size, the size of a few atoms. The question of crucial importance in the physics of utilization of nanotubes ... 
Microfabrication of micro Hall sensors on GaAs and INSB for scanning hall probe microscopy
(Bilkent University, 2001)Different techniques have been developed to investigate the surface magnetic structure of materials, including Hall probe, scanning superconductivity quantum interference device (SQUID) and magnetic force microscopies ... 
Microfluidic based differential electrochemical sensors
(Bilkent University, 2013)Labonachip systems aim to integrate analytical techniques on a single chip to achieve highthroughput measurements with little reagent. Microfluidic devices use the advantage of fluid dynamics in microscale to generate ...