**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**115

# Search results for: quantum well

##### 115 A Programmer’s Survey of the Quantum Computing Paradigm

**Authors:**
Philippe Jorrand

**Abstract:**

Research in quantum computation is looking for the consequences of having information encoding, processing and communication exploit the laws of quantum physics, i.e. the laws which govern the ultimate knowledge that we have, today, of the foreign world of elementary particles, as described by quantum mechanics. This paper starts with a short survey of the principles which underlie quantum computing, and of some of the major breakthroughs brought by the first ten to fifteen years of research in this domain; quantum algorithms and quantum teleportation are very biefly presented. The next sections are devoted to one among the many directions of current research in the quantum computation paradigm, namely quantum programming languages and their semantics. A few other hot topics and open problems in quantum information processing and communication are mentionned in few words in the concluding remarks, the most difficult of them being the physical implementation of a quantum computer. The interested reader will find a list of useful references at the end of the paper.

**Keywords:**
Quantum information processing,
quantum algorithms,
quantum programming languages.

##### 114 Numerical Calculation of the Ionization Energy of Donors in a Cubic Quantum well and Wire

**Authors:**
Sara Sedaghat,
Mahmood Barati,
Iraj Kazeminezhad

**Abstract:**

**Keywords:**
quantum well,
quantum wire,
quantum dot,
impuritystate

##### 113 An Authentication Protocol for Quantum Enabled Mobile Devices

**Authors:**
Natarajan Venkatachalam,
Subrahmanya V. R. K. Rao,
Vijay Karthikeyan Dhandapani,
Swaminathan Saravanavel

**Abstract:**

**Keywords:**
Quantum cryptography,
quantum key distribution,
wireless quantum communication,
authentication protocol,
quantum
enabled device,
trusted third party.

##### 112 A Post Processing Method for Quantum Prime Factorization Algorithm based on Randomized Approach

**Authors:**
Mir Shahriar Emami,
Mohammad Reza Meybodi

**Abstract:**

**Keywords:**
Quantum Prime Factorization,
RandomizedAlgorithms,
Quantum Computer Simulation,
Quantum Computation.

##### 111 The Magnetized Quantum Breathing in Cylindrical Dusty Plasma

**Authors:**
A. Abdikian

**Abstract:**

**Keywords:**
The linear quantum hydrodynamic model,
the magnetized quantum breathing mode,
the quantum dispersion relation of rotation mode,
void structure.

##### 110 A Computer Model of Quantum Field Theory

**Authors:**
Hans H. Diel

**Abstract:**

This paper describes a computer model of Quantum Field Theory (QFT), referred to in this paper as QTModel. After specifying the initial configuration for a QFT process (e.g. scattering) the model generates the possible applicable processes in terms of Feynman diagrams, the equations for the scattering matrix, and evaluates probability amplitudes for the scattering matrix and cross sections. The computations of probability amplitudes are performed numerically. The equations generated by QTModel are provided for demonstration purposes only. They are not directly used as the base for the computations of probability amplitudes. The computer model supports two modes for the computation of the probability amplitudes: (1) computation according to standard QFT, and (2) computation according to a proposed functional interpretation of quantum theory.

**Keywords:**
Computational Modeling,
Simulation of Quantum Theory,
Quantum Field Theory,
Quantum Electrodynamics

##### 109 Proposal of Optimality Evaluation for Quantum Secure Communication Protocols by Taking the Average of the Main Protocol Parameters: Efficiency, Security and Practicality

**Authors:**
Georgi Bebrov,
Rozalina Dimova

**Abstract:**

**Keywords:**
Quantum cryptography,
quantum secure
communcation,
quantum secure direct communcation security,
quantum secure direct communcation efficiency,
quantum secure
direct communcation practicality.

##### 108 Behavior of Current in a Semiconductor Nanostructure under Influence of Embedded Quantum Dots

**Authors:**
H. Paredes Gutiérrez,
S. T. Pérez-Merchancano

**Abstract:**

Motivated by recent experimental and theoretical developments, we investigate the influence of embedded quantum dot (EQD) of different geometries (lens, ring and pyramidal) in a double barrier heterostructure (DBH). We work with a general theory of quantum transport that accounts the tight-binding model for the spin dependent resonant tunneling in a semiconductor nanostructure, and Rashba spin orbital to study the spin orbit coupling. In this context, we use the second quantization theory for Rashba effect and the standard Green functions method. We calculate the current density as a function of the voltage without and in the presence of quantum dots. In the second case, we considered the size and shape of the quantum dot, and in the two cases, we worked considering the spin polarization affected by external electric fields. We found that the EQD generates significant changes in current when we consider different morphologies of EQD, as those described above. The first thing shown is that the current decreases significantly, such as the geometry of EQD is changed, prevailing the geometrical confinement. Likewise, we see that the current density decreases when the voltage is increased, showing that the quantum system studied here is more efficient when the morphology of the quantum dot changes.

**Keywords:**
Quantum semiconductors,
nanostructures,
quantum dots,
spin polarization.

##### 107 1/f Noise in Quantum-Size Heteronanostructures Based On GaAs and Alloys

**Authors:**
Alexey V. Klyuev,
Arkady. V. Yakimov

**Abstract:**

The 1/f noise investigation in nanoscale light-emitting diodes and lasers, based on GaAs and alloys, is presented here. Leakage and additional (to recombination through quantum wells and/or dots) nonlinear currents were detected and it was shown that these currents are the main source of the 1/f noise in devices studied.

**Keywords:**
Lasers,
light-emitting diodes,
quantum dots,
quantum wells,
1/f noise.

##### 106 A method of Authentication for Quantum Networks

**Authors:**
Stefan Rass

**Abstract:**

**Keywords:**
Meet-in-the-middle attack,
quantum key distribution,
quantum networks,
unconditionally secure authentication.

##### 105 Entanglement-based Quantum Computing by Diagrams of States

**Authors:**
Sara Felloni,
Giuliano Strini

**Abstract:**

**Keywords:**
Diagrams of states,
entanglement,
quantum circuits,
quantum information.

##### 104 Propagation of Nonlinear Surface Waves in Relativistically Degenerate Quantum Plasma Half-Space

**Authors:**
Swarniv Chandra,
Parthasona Maji,
Basudev Ghosh

**Abstract:**

The nonlinear self-interaction of an electrostatic surface wave on a semibounded quantum plasma with relativistic degeneracy is investigated by using quantum hydrodynamic (QHD) model and the Poisson’s equation with appropriate boundary conditions. It is shown that a part of the second harmonic generated through self-interaction does not have a true surface wave character but propagates obliquely away from the plasma-vacuum interface into the bulk of plasma.

**Keywords:**
Harmonic Generation,
Quantum Plasma,
Quantum Hydrodynamic Model,
Relativistic Degeneracy,
Surface waves.

##### 103 Instability of Electron Plasma Waves in an Electron-Hole Bounded Quantum Dusty Plasma

**Authors:**
Basudev Ghosh,
Sailendranath Paul,
Sreyasi Banerjee

**Abstract:**

Using quantum hydrodynamical (QHD) model the linear dispersion relation for the electron plasma waves propagating in a cylindrical waveguide filled with a dense plasma containing streaming electron, hole and stationary charged dust particles has been derived. It is shown that the effect of finite boundary and stream velocity of electrons and holes make some of the possible modes of propagation linearly unstable. The growth rate of this instability is shown to depend significantly on different plasma parameters.

**Keywords:**
Electron Plasma wave,
Quantum plasma,
Quantum Hydrodynamical model.

##### 102 Unconditionally Secure Quantum Payment System

**Authors:**
Essam Al-Daoud

**Abstract:**

A potentially serious problem with current payment systems is that their underlying hard problems from number theory may be solved by either a quantum computer or unanticipated future advances in algorithms and hardware. A new quantum payment system is proposed in this paper. The suggested system makes use of fundamental principles of quantum mechanics to ensure the unconditional security without prior arrangements between customers and vendors. More specifically, the new system uses Greenberger-Home-Zeilinger (GHZ) states and Quantum Key Distribution to authenticate the vendors and guarantee the transaction integrity.

**Keywords:**
Bell state,
GHZ state,
Quantum key distribution,
Quantum payment system.

##### 101 Nonplanar Ion-acoustic Waves in a Relativistically Degenerate Quantum Plasma

**Authors:**
Swarniv Chandra,
Sibarjun Das,
Agniv Chandra,
Basudev Ghosh,
Apratim Jash

**Abstract:**

**Keywords:**
Kadomtsev-Petviashvili equation,
Ion-acoustic
Waves,
Relativistic Degeneracy,
Quantum Plasma,
Quantum
Hydrodynamic Model.

##### 100 Quantum Computing: A New Era of Computing

**Authors:**
Jyoti Chaturvedi Gursaran

**Abstract:**

Nature conducts its action in a very private manner. To reveal these actions classical science has done a great effort. But classical science can experiment only with the things that can be seen with eyes. Beyond the scope of classical science quantum science works very well. It is based on some postulates like qubit, superposition of two states, entanglement, measurement and evolution of states that are briefly described in the present paper. One of the applications of quantum computing i.e. implementation of a novel quantum evolutionary algorithm(QEA) to automate the time tabling problem of Dayalbagh Educational Institute (Deemed University) is also presented in this paper. Making a good timetable is a scheduling problem. It is NP-hard, multi-constrained, complex and a combinatorial optimization problem. The solution of this problem cannot be obtained in polynomial time. The QEA uses genetic operators on the Q-bit as well as updating operator of quantum gate which is introduced as a variation operator to converge toward better solutions.

**Keywords:**
Quantum computing,
qubit,
superposition,
entanglement,
measurement of states,
evolution of states,
Scheduling
problem,
hard and soft constraints,
evolutionary algorithm,
quantum
evolutionary algorithm.

##### 99 Novel Design of Quantum Dot Arrays to Enhance Near-Fields Excitation Resonances

**Authors:**
N. H. Ismail,
A. A. A. Nassar,
K. H. Baz

**Abstract:**

Semiconductor crystals smaller than about 10 nm, known as quantum dots, have properties that differ from large samples, including a band gap that becomes larger for smaller particles. These properties create several applications for quantum dots. In this paper new shapes of quantum dot arrays are used to enhance the photo physical properties of gold nano-particles. This paper presents a study of the effect of nano-particles shape, array, and size on their absorption characteristics.

**Keywords:**
Quantum Dots,
Nano-Particles,
LSPR.

##### 98 A Functional Interpretation of Quantum Theory

**Authors:**
Hans H. Diel

**Abstract:**

**Keywords:**
Computability,
Foundation of Quantum Mechanics,
Measurement Problem,
Models of Physics.

##### 97 The Hall Coefficient and Magnetoresistance in Rectangular Quantum Wires with Infinitely High Potential under the Influence of a Laser Radiation

**Authors:**
Nguyen Thu Huong,
Nguyen Quang Bau

**Abstract:**

**Keywords:**
Hall coefficient,
rectangular quantum wires,
electron-optical phonon interaction,
quantum kinetic equation.

##### 96 A Quantum Algorithm of Constructing Image Histogram

**Authors:**
Yi Zhang,
Kai Lu,
Ying-hui Gao,
Mo Wang

**Abstract:**

**Keywords:**
Quantum Image Representation,
Quantum
Algorithm,
Image Histogram.

##### 95 Problems and Possible Solutions with the Development of a Computer Model of Quantum Theory

**Authors:**
Hans H. Diel

**Abstract:**

**Keywords:**
Computability,
Foundation of Quantum Mechanics,
Measurement Process,
Modeling.

##### 94 Discontinuous Spacetime with Vacuum Holes as Explanation for Gravitation, Quantum Mechanics and Teleportation

**Authors:**
Constantin Z. Leshan

**Abstract:**

Hole Vacuum theory is based on discontinuous spacetime that contains vacuum holes. Vacuum holes can explain gravitation, some laws of quantum mechanics and allow teleportation of matter. All massive bodies emit a flux of holes which curve the spacetime; if we increase the concentration of holes, it leads to length contraction and time dilation because the holes do not have the properties of extension and duration. In the limited case when space consists of holes only, the distance between every two points is equal to zero and time stops - outside of the Universe, the extension and duration properties do not exist. For this reason, the vacuum hole is the only particle in physics capable of describing gravitation using its own properties only. All microscopic particles must 'jump' continually and 'vibrate' due to the appearance of holes (impassable microscopic 'walls' in space), and it is the cause of the quantum behavior. Vacuum holes can explain the entanglement, non-locality, wave properties of matter, tunneling, uncertainty principle and so on. Particles do not have trajectories because spacetime is discontinuous and has impassable microscopic 'walls' due to the simple mechanical motion is impossible at small scale distances; it is impossible to 'trace' a straight line in the discontinuous spacetime because it contains the impassable holes. Spacetime 'boils' continually due to the appearance of the vacuum holes. For teleportation to be possible, we must send a body outside of the Universe by enveloping it with a closed surface consisting of vacuum holes. Since a material body cannot exist outside of the Universe, it reappears instantaneously in a random point of the Universe. Since a body disappears in one volume and reappears in another random volume without traversing the physical space between them, such a transportation method can be called teleportation (or Hole Teleportation). It is shown that Hole Teleportation does not violate causality and special relativity due to its random nature and other properties. Although Hole Teleportation has a random nature, it can be used for colonization of extrasolar planets by the help of the method called 'random jumps': after a large number of random teleportation jumps, there is a probability that the spaceship may appear near a habitable planet. We can create vacuum holes experimentally using the method proposed by Descartes: we must remove a body from the vessel without permitting another body to occupy this volume.

**Keywords:**
Border of the universe,
causality violation,
perfect isolation,
quantum jumps.

##### 93 Hall Coefficient in the Presence of Strong Electromagnetic Waves Caused by Confined Electrons and Phonons in a Rectangular Quantum Wire

**Authors:**
Nguyen Quang Bau,
Nguyen Thu Huong,
Dang Thi Thanh Thuy

**Abstract:**

**Keywords:**
Hall coefficient,
rectangular quantum wires,
electron-optical phonon interaction,
quantum kinetic equation,
confined phonons.

##### 92 Eight-State BB84: A C# Simulation

**Authors:**
Liliana Zisu

**Abstract:**

The first and best known quantum protocol BB84, whose security is unconditional allows the transmission of a key with a length equal to that of the message. This key used with an encryption algorithm leads to an unbreakable cryptographic scheme. Despite advantages the protocol still can be improved in at least two aspects: its efficiency which is of about 50%, only half of the photons transmitted are used to create the encryption key and the second aspect refers to the communication that takes place on the classic channel, as it must be reduced or even eliminated. The paper presents a method that improves the two aspects of the BB84 protocol by using quantum memory and eight states of polarization. The implementation of both the proposed method and the BB84 protocol was done through a C# application.

**Keywords:**
BB84,
protocol,
quantum cryptography,
quantum key distribution.

##### 91 Ovshinsky Effect by Quantum Mechanics

**Authors:**
Thomas V. Prevenslik

**Abstract:**

**Keywords:**
Ovshinsky,
phase change memory,
PC-RAM,
chalcogenide,
quantummechanics,
quantum electrodynamics.

##### 90 Characterization of InGaAsP/InP Quantum Well Lasers

**Authors:**
K. Melouk,
M. Dellakrachai

**Abstract:**

**Keywords:**
Laser,
quantum well,
semiconductor,
InGaAsP.

##### 89 Influence of an External Magnetic Field on the Acoustomagnetoelectric Field in a Rectangular Quantum Wire with an Infinite Potential by Using a Quantum Kinetic Equation

**Authors:**
N. Q. Bau,
N. V. Nghia

**Abstract:**

The acoustomagnetoelectric (AME) field in a rectangular quantum wire with an infinite potential (RQWIP) is calculated in the presence of an external magnetic field (EMF) by using the quantum kinetic equation for the distribution function of electrons system interacting with external phonons and electrons scattering with internal acoustic phonon in a RQWIP. We obtained ananalytic expression for the AME field in the RQWIP in the presence of the EMF. The dependence of AME field on the frequency of external acoustic wave, the temperature *T* of system, the cyclotron frequency of the EMF and the intensity of the EMF is obtained. Theoretical results for the AME field are numerically evaluated, plotted and discussed for a specific RQWIP *GaAs/GaAsAl*. This result has shown that the dependence of the AME field on intensity of the EMF is nonlinearly and it is many distinct maxima in the quantized magnetic region. We also compared received fields with those for normal bulk semiconductors, quantum well and quantum wire to show the difference. The influence of an EMF on AME field in a RQWIP is newly developed.

**Keywords:**
Rectangular quantum wire,
acoustomagnetoelectric field,
electron-phonon interaction,
kinetic equation method.

##### 88 Performance Analysis of Quantum Cascaded Lasers

**Authors:**
M. B. El_Mashade,
I. I. Mahamoud,
M. S. El_Tokhy

**Abstract:**

Improving the performance of the QCL through block diagram as well as mathematical models is the main scope of this paper. In order to enhance the performance of the underlined device, the mathematical model parameters are used in a reliable manner in such a way that the optimum behavior was achieved. These parameters play the central role in specifying the optical characteristics of the considered laser source. Moreover, it is important to have a large amount of radiated power, where increasing the amount of radiated power represents the main hopping process that can be predicted from the behavior of quantum laser devices. It was found that there is a good agreement between the calculated values from our mathematical model and those obtained with VisSim and experimental results. These demonstrate the strength of mplementation of both mathematical and block diagram models.

**Keywords:**
Quantum Cascaded Lasers (QCLs),
Modeling,
Block Diagram Programming,
Intersubband transitions

##### 87 High Performance In0.42Ga0.58As/In0.26Ga0.74As Vertical Cavity Surface Emitting Quantum Well Laser on In0.31Ga0.69As Ternary Substrate

**Authors:**
Md. M. Biswas,
Md. M. Hossain,
Shaikh Nuruddin

**Abstract:**

**Keywords:**
Quantum well,
VCSEL,
output power,
materialgain,
modulation bandwidth.

##### 86 Higher-Dimensional Quantum Cryptography

**Authors:**
Bradley Christensen,
Kevin T. McCusker,
Daniel J. Gauthier,
Daniel Kumor,
Venkat Chandar,
P. G. Kwiat

**Abstract:**

**Keywords:**
Downconversion,
Hyper-entanglement,
Quantum Cryptography