Browsing Theses - Department of Physics by Title
Now showing items 22-41 of 233
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Calculation of masses of dark solitons in 1D Bose-Einstein condensates using Gelfand Yaglom method
(Bilkent University, 2016-11)Nonlinear excitations of Bose-Einstein condensates (BEC) play important role in understanding the dynamics of BECs. Solitons, shape preserving wave packets, are the most fundamental nonlinear excitations of BECs. They ... -
Carrier dynamics in silicon and Germanium nanocrystals
(Bilkent University, 2008)This is a computational work on the Si and Ge nanocrystals (NCs) embedded in wide band gap host matrices. As the initial task, extensive ab initio work on the structural and electronic properties of various NC host ... -
Chalcogenide micro and nanostructures and applications
(Bilkent University, 2014)Chalcogenides, which are glasses consist of S, Se and Te elements, are promising materials for photonics as silicon for modern electronics, due to their extraordinary material properties such as high nonlinearity and ... -
Characterization and applications of negative-index metamaterials
(Bilkent University, 2008)Metamaterials offer novel electromagnetic properties and promising applications including negative refraction, flat-lenses, superlenses, cloaking devices. In this thesis, we characterized the negative-index metamaterials ... -
Characterization of photonic crystals at microwave frequencies
(Bilkent University, 1996)VVe investigated the surface reflection properties of layer-by-layer photonic crystals, for dielectric and metallic based photonic crystals. By using a FabryPerot cavity analogy with the reflection-phase information of ... -
Computational study of excitons and biexcitons in semiconductor core/shell nanocrystals of type I and type II
(Bilkent University, 2013)In this thesis, we studied electronic structure and optical properties of Type-I, Type-II, and quasi Type-II semiconductor nanocrystals (also known as colloidal quantum dots). For a parametric study, we developed quantum ... -
Construction of a scanning tunneling microscope and first results
(Bilkent University, 1990)In this thesis, construction of a Scanning Tunneling Microscope in air is explained. A step motor sample approach mechanism and a tripod scanner are used in the construction. Atomic resolution images of graphite samples ... -
Construction of an atomic force microscope operating in air and liquid
(Bilkent University, 2003)In this thesis, a new atomic force microscope capable of measuring in liquid and air has been introduced. The highly improved design of the instrument eliminates some of the technical problems which are occurred before. ... -
Controlled lateral and perpendicular motion of atoms on metal surfaces
(Bilkent University, 1994)Nanoscale modification of matter has been the subject of interest. Recently, several experimental studies have demonstrated that by using a scanning tunneling microscope one can translate atoms on metal surfaces to a ... -
Controlling electromagnetic waves with active graphene devices
(Bilkent University, 2015) -
Correlation effects in coupled quantum-well and quantum-wire systems
(Bilkent University, 2001) -
Dark current control in InAs/GaSb superlattice photodetectors
(Bilkent University, 2013)Bose-Einstein Condensation (BEC) was introduced by Einstein 1925. It took 70 years to confirm BEC by experiments. BEC creates a suitable environment to observe macroscopic-quantum behavior. Condensates consist of ultracold ... -
Decoherence in open quantum systems : a realistic approach
(Bilkent University, 2006)Decoherence mechanisms of opcu quantum systems ın intcraction with an enviromental bath is investigated using the master equation formalism. Widely used two-level approximation is questioned. -
Deformation and finite size effects in cooperative molecular motors
(Bilkent University, 2002-07)Motor protein systems have been of considerable interest lately. In these studies muscle contraction is modeled as the sliding of two filaments made of protein particles over one another, that is the sliding of the ... -
Development of force fields for novel 2D materials for temperature dependent vibrational properties
(Bilkent University, 2019-09)A new era of nanodevice engineering has been started after fabricating graphene. This motivated vast number of researches for predicting, fabricating and utilizing 2D materials. Temperature dependent properties are ... -
Development of nano hall sensors for high resolution scanning hall probe microscopy
(Bilkent University, 2008) -
Dipolar bose-einstein condensate in a cylindrically symmetric trap
(Bilkent University, 2016-08)Bose-Einstein Condensate (BEC) and particularly its stability dynamics has been a subject to many investigations since the first realization of this new condensed state in alkali atoms interacting via short range potential. ... -
Dynamical effects of noise on nonlinear systems
(Bilkent University, 2014)Randomness and nonlinear dynamics consitute the most essential part of many events in nature. Therefore, a better and comprehensive understanding of them is a crucial step in describing natural phenomena as well as the ... -
Dynamics of a two leg ladder under a time dependent artificial magnetic field
(Bilkent University, 2019-09)Especially in the last two decades, there have been intensive theoretical and experimental studies on the periodically driven quantum systems. The reasons for these intensive studies are the emergence of new topological ... -
Electro-magnetic properties and phononic energy dissipation in graphene based structures
(Bilkent University, 2008)With the synthesis of a single atomic plane of graphite, namely graphene honeycomb structure, active research has been focused on the massless Dirac fermion behavior and related artifacts of the electronic bands crossing ...