X Preface
In chapter 1.3 Yi Chen et al. analysed EIT and EIT-based slow light in a Doppler-
broadened six-level atomic system of
87
Rb D2 line. The EIT dip shift due to the
existence of the neighbouring levels was investigated. Authors of this study offered a
better comprehension of the slow light phenomenon in the complicated multi-level
system. They also showed a system whose hyperfine states were closely spaced within
the Doppler broadening for potential applications of optical and quantum information
processing, such as multichannel all-optical buffer memories and slow-light-based
enhanced cross-phase modulation. An N-type system and numerical simulation of
slow light phenomenon in this kind of system were also presented. The importance of
EIT and the slow light phenomenon in multilevel system was explained and it showed
potential applications in the use of ultraslow light for optical information processing
such as all-optical multichannel buffer memory and quantum gate based on enhanced
cross-phase modulation owing to increased interaction time between two slow-light
pulses.
In chapter 1.4 coauthored by Dipti Gupta et al. a new class of electronic materials for
thin film transistor (TFT) applications such as active matrix displays, identification
tags, sensors and other low end consumer applications were illustrated. Authors
explained the importance of two dimensional simulations in both classes of materials
by aiming at several common issues, which were not clarified enough by experimental
means or by analytical equations. It started with modeling of TFTs based on tris-
isopropylsilyl (TIPS) – pentacene to supply a baseline to describe the charge transport
in any new material. The role of metal was stressed and then the stability issue in
solution processable zinc oxide (ZnO) TFTs was taken into consideration. To sum up,
the important role of device simulations for a better understanding of the material
properties and device mechanisms was recognized in TFTs and it was based on
organic and metal oxide semiconductors. By providing illustrations from pentacene,
the effect of physical behavior which was related to semiconductor film properties in
relation to charge injection and charge transport was underlined, TIPS- pentacene and
ZnO based TFTs. The device simulations brightened the complex device phenomenon
that occurred at the metal-semiconductor interface, semiconductor-dielectric interface,
and in the semiconductor film in the form of defect distribution.
The main subjects summarized by Wenlong He et al. of chapter 1.5 were: the
simulations and optimizations of a W-band gyro-BWO including the simulation of a
thermionic cusp electron gun which generated an annular, axis-encircling electron
beam. The optimization of the W-band gyro-BWO was presented by using the 3D PiC
(particle-in-cell) code MAGIC. The MAGIC simulated the interaction between charged
particles and electromagnetic fields as they evolved in time and space from the initial
states. Fields in the three-dimensional grids were solved by Maxwell equations. The
other points which were introduced were: the simulation of the beam-wave interaction
in the helically corrugated interaction region and the simulation and optimization of
an energy recovery system of 4-stage depressed collector.
Paul Horley et al. in chapter 1.6 analyzed different representations (spherical,
Cartesian, stereographic and Frenet-Serret) of the Landau-Lifshitz-Gilbert equation