We will prove the existence of a universal quantum cellular automaton. Such qca are defined as the quantum-mechanical pendant of classical one-dimensional cellular automata. As is the case with quantum Turing machines, the well-formedness restriction plays an important role. It will be shown that every proper qca obeys a local constraint which is comparable with the ‘inverse neighborhood’ of cl...

Quantum-dot Cellular Automata (QCA) is a promising, emerging nanotechnology based on single electron effects in quantum dots and molecules. While many logic implementations based on QCA devices have been proposed in literature [6, 7, 8], the inherent cellular structure of QCA cells make it a natural candidate for Cellular Automata (CA) implementation. CA offers regularity and modularity to the ...

Quantum-dot Cellular Automata (QCA) is a prominent paradigm that is considered to continue its dominance in thecomputation at deep sub-micron regime in nanotechnology. The QCA realizations of five-input Majority Voter based multilevel parity generator circuits have been introduced in recent years. However, no attention has been paid towards the QCA instantiation of the generic (n-bit) even and ...

Quantum dot cellular automata (QCA) introduces a pioneer technology in nano scale computer architectures. Employing this technology is one of the solutions to decrease the size of circuits and reducing power dissipation. In this paper, two new optimized FlipFlops with reset input are proposed in quantum dot cellular automata technology. In addition, comparison with related works is performed.Th...

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 one of the important nano-level technologies for implementation of both combinational and sequential systems. qca have the potential to achieve low power dissipation and operate high speed at thz frequencies. however large probability of occurrence fabrication defects in qca, is a fundamental challenge to use this emerging technology. because of these vari...

Today, the use of CMOS technology for the manufacture of electronic ICs has faced many limitations. Many alternatives to CMOS technology are offered and made every day. Quantum-dot cellular automata (QCA) is one of the most widely used. QCA gates and circuits have many advantages including small size, low power consumption and high speed. On the other hand, using special digital gates called re...

Recently testing of Quantum-dot Cellular Automata (QCA) Circuits has attracted a lot of attention. In this paper, QCA is investigated for testable implementations of reversible logic. To amplify testability in Reversible QCA circuits, a test method regarding to Built In Self Test technique is developed for detecting all simulated defects. A new Reversible QCA MUX 2×1 desig...

I. Outline 1 II. Glossary 2 III. Definition of the subject and its importance 2 IV. Introduction 2 V. Cellular Automata 3 A. Reversible Cellular Automata 4 VI. Early proposals 4 VII. Definition 6 VIII. Models of QCA 6 A. Reversible QCA 6 B. Local unitary QCA 7 C. Block-partitioned and nonunitary QCA 7 D. Continuous-time QCA 8 E. Examples of QCA 8 IX. Computationally universal QCA 9 X. Modeling ...

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...