Quantum-dot cellular automata ~QCA!, arrays of coupled quantum-dot devices, are proposed for quantum computing. The notion of coherent QCA ~CQCA! is introduced in order to distinguish QCA applied to quantum computing from classical digital QCA. Information is encoded in the spatial state of the electrons in the multidot system. A line of CQCA cells can work as a quantum register. The basic sing...

This paper proposes a SPICE model development methodology for quantum-dot cellular automata (QCA) cells and presents a SPICE model for QCA cells. The model is validated by simulating the basic logic gates such as inverter and majority voter. The proposed model makes it possible to design and simulate QCA combinational circuits and hybrid circuits of QCA and other NANO devices using SPICE. In th...

We give a one-dimensional quantum cellular automata (QCA) capable of simulating all others. By this we mean that the initial configuration and the local transition rule of any one-dimensional QCA can be encoded within the initial configuration of the universal QCA. Several steps of the universal QCA will then correspond to one step of the simulated QCA. The simulation preserves the topology in ...

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...

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 ...

The notion of quantum-dot cellular automata (QCA) as a possible replacement paradigm for conventional transistor-based logic is reviewed. Experiments using metal tunnel structures demonstrating a functional QCA cell are presented. It is shown that single electron tunnelling transistors used as electrometers verify proper switching of the QCA cell. Additionally, we provide evidence for a QCA cel...

In order to design large digital circuits using Quantum-Dot Cellular Automata(QCA) cells, CAD tools and automated design methodology for QCA circuits are essential. This paper presents a QCA circuits design methodology based on traditional CMOS circuits design flow. This QCA circuits design methodology utilizes the current CMOS circuits design tools such as HSPICE and Synopsys Design Compiler. ...

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...

Physical limitations of Complementary Metal-Oxide-Semiconductors (CMOS) technology at nanoscale and high cost of lithography have provided the platform for creating Quantum-dot Cellular Automata (QCA)-based hardware. The QCA is a new technology that promises smaller, cheaper and faster electronic circuits, and has been regarded as an effective solution for scalability problems in CMOS technolog...

Quantum-dot cellular automata (QCA) is an emerging technology which has been claimed to be faster and smaller than the most traditional CMOS technology. Since its beginning, many advances have been made, as the introduction of basic devices and the insertion of more complex circuits, like adders. It is not straightforward to implement more complex adders using QCA. This paper proposes the logic...