Classical physics breaks down to the level of atoms and molecules. This was made
possible by the invention of a new apparatus that enabled the introduction of
measurements in microscopic area of physics. There were two revolutions in the way
we viewed the physical world in the twentieth century: relativity and quantum
mechanics. Quantum mechanics was born in 1924, through the work of Einstein,
Rutherford and Bohr, Schrödinger and Heisenberg, Born, Dirac, and many others. The
principles of quantum mechanics that were discovered then are the same as we know
The density matrix offers an effective technique for dealing statistically with a
system consisting of many electrons using the quantum theory for an electron.
Amixed state consisting of a statistical distribution of various quantum states
can be specified by a set of probabilities pj with which the electron is found
in a quantum state j ji.
A new type of semiconductor laser is studied, in which injected carriers in the active region
are quantum mechanically confined in localized finite self-assembled wire-like quantumdash
(Qdash) structures that are varied in sizes and compositions. Effects of such carrier
distribution and quasi three-dimensional density of states contribute to a quasisupercontinuum
interband lasing characteristics, which is a new laser design platform as
compared to continuous broad emission spectrum generated by nonlinear media pumped
with ultrashort laser pulse....
This book is a collection of some of the invited talks presented at the international
meeting held at the Max Planck Institut fiir Physik komplexer Systeme, Dresden,
Germany during August 6-30, 2001, on the rapidly developing field of nanoscale
science and bio-electronics (http://www.mpipks-dresden.mpg.de/~nanobio/).
Semiconductor physics has experienced unprecedented developments over the second
half of the twentieth century. The exponential growth in microelectronic processing
power and the size of dynamic memories has been achieved by significant downscahng
of the minimum feature size.
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Selective area epitaxy of ultra-high density InGaN quantum dots by diblock copolymer lithography
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài:
Temperature and electron density dependence of spin relaxation in GaAs/AlGaAs quantum well
Chemical reactions take place due to the redistribution of electron density among the
reacting partners. Focusing on changes in electron density, which accompany the
breaking and forming of chemical bonds, instead of the changes in the wave function
accompanying them, allows us to use the ‘‘classical’’ three-dimensional language.
Conceptual density functional theory (DFT) quantifies the possible responses of the
system to various changes in density.
This chapter presents the basic theory and characteristics of stimulated
emission and optical amplification gain in semiconductors. The former is the
mostimportant principlethat enablessemiconductorlaserstobeimplemented,
and the latter is the most important parameter for analysis of the laser
performances. First, stimulated emission in semiconductors is explained, and
then quantum theory analysis and statistic analysis using the density matrix
of the optical amplification gain are given.
Integrative evolving connectionist systems (iECOS) integrate principles
from different levels of information processing in the brain, including cognitive-,
neuronal-, genetic- and quantum, in their dynamic interaction over time. The paper
introduces a new framework of iECOS called integrative probabilistic evolving
spiking neural networks (ipSNN) that incorporate probability learning parameters.
ipSNN utilize a quantum inspired evolutionary optimization algorithm to optimize
the probability parameters as these algorithms belong to the class of estimation of
distribution algorithms (EDA).