Novel digital technologies always lead to high density and very low power consumption. One of these concepts is Quantum-dot Cellular Automata (QCA), which is one of the new emerging nanotechnology-based on Coulomb repulsion. This article presents three architectures of logical “XOR” gate, a novel structure of two inputs “XOR” gate, which is used as a module to implement four inputs “XOR” gate a...

Application of quantum-dot is a promising technology for implementing digital systems at nano-scale.  Quantum-dot Cellular Automata (QCA) is a system with low power consumption and a potentially high density and regularity. Also, QCA supports the new devices with nanotechnology architecture. This technique works </...

Quantum dot cellular automata(QCA) shows promise as a post silicon CMOS,low power computational technology.Nevertheless,to generalize QCA for next generation digital devices,the ability to implement conventional programmable circuits based on NOR,AND and OR gates is necessary.We devise a new QCA structure,the QCA multiplier,employing the five quantum dot QCA cell.The structure can multiply two ...

We discuss the fundamental limits of computing using a new paradigm for quantum computation, cellular automata composed of arrays of Coulombically coupled quantum dot molecules, which we term quantum cellular automata (QCA). Any logical or arithmetic operation can be performed in this scheme. QCA’s provide a valuable concrete example of quantum computation in which a number of fundamental issue...

The computational paradigm known as quantum-dot cellular automata (QCA) encodes binary information in the charge configuration of Coulomb-coupled quantum-dot cells. Functioning QCA devices made of metal-dot cells have been fabricated and measured. We focus here on the issue of robustness in the presence of disorder and thermal fluctuations. We examine the performance of a semi-infinite QCA shif...

Quantum-dot Cellular Automata (QCA) is an emerging and promising technology that provides significant improvements over CMOS. Recently QCA has been advocated as an applicant for implementing reversible circuits. However QCA, like other Nanotechnologies, suffers from a high fault rate. The main purpose of this paper is to develop a fault tolerant model of QCA circuits by redundancy in hardware a...

Quantum-Dot Cellular Automata (QCA) is a computational scheme utilizing the position of interacting single electrons within arrays of quantum dots ("cells") to encode and process binary information. Clocked QCA architectures can provide power gain, logic level restoration, and memory features. Using arrays of micron-sized metal dots, we experimentally demonstrate operation of a QCA latch-invert...

In this paper, the different types of logical structure based on Quantum dot Cellular Automata (QCA) design are discussed. The QCA offers a new transistorless computing paradigm in nanotechnology. It has the potential for attractive features such as faster speed , smaller size and low power consumption than transistor based technology .By taking the advantages of QCA we are able to design inter...

Quantum-dot cellular automata (QCA) are an emerging technology and a possible alternative for faster speed, smaller size, and low power consumption than semiconductor transistor based technologies. Previously, adder designs based on conventional designs were examined for implementation with QCA technology. This paper utilizes the QCA characteristics to design a fault-tolerant adder that is more...

Quantum-dot cellular automata (QCA) is a digital logic architecture that uses single electrons in arrays of quantum dots to perform binary operations. A QCA latch is an elementary building block which can be used to build shift registers and logic devices for clocked QCA architectures. We discuss the operation of a QCA latch and a shift register and present an analysis of the types and properti...