The quantum-dot cellular automata (QCA) computational paradigm provides a means to achieve ultimately low limits of power dissipation by replacing binary coding in currents and voltages with single-electron switching within arrays of quantum dots (‘‘cells’’). Clocked control over the cells allows the realization of power gain, memory and pipelining in QCA circuits. We present an experimental de...

Quantum-dot cellular automata ~QCA! involves representing binary information with the charge configuration of closed cells comprised of several dots. Current does not flow between cells, but rather the Coulomb interaction between cells enables computation to occur. We use this system to explore, quantitatively and in a specific physical system, the relation between computation and energy dissip...

In the near future the era of Beyond CMOS will start as the scaling of the current CMOS technology will reach the fundamental limit. QCA (Quantum-dot Cellular Automata) is the transistor less computation paradigm and viable candidate for Beyond CMOS device technology. The complete state of art survey on QCA is presented in this paper. This paper addresses the QCA background, its possible implem...

Quantum-dot cellular automata ~QCA! may provide a novel way to bypass the transistor paradigm to form ultrasmall computing elements. In the QCA paradigm information is represented in the charge configuration of a QCA cell, which maps naturally to a binary model. Molecular QCA implementations are being explored where the quantum dots in the cell take the form of redox centers in a molecule. Cloc...

The use of quantum-dots is a promising emerging technology for implementing digital systems at the nano-scale level. Recently studied computational paradigms for quantum-dot technology include the use of locally connected quantum-dot cellular automata (QCA). This technique is based on the interaction of electrons within quantum dots that take advantage of quantum phenomena; the same phenomena t...

by Géza Tóth In this thesis we investigate the role of correlation and coherence in two possible realizations of Quantum-dot Cellular Automata (QCA): realizations as a semiconductor multi-quantum-dot structure and as a metal-island single electron tunneling circuit. The two are different from the point of view of the underlying physics. The metal island circuits are very strongly connected to t...

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...

Due to the superior photoemission and photostability characteristics, quantum dots (QD) are novel tools in biological and medical applications. However, the toxicity and mechanism of QD uptake are poorly understood. QD nanoparticles with an emission wavelength of 655 nm are ellipsoid in shape and consist of a cadmium/selenide core with a zinc sulfide shell. We have shown that QD with a carboxyl...

Quantum-dot Cellular Automata (QCA) can be considered as a candidate for the next generation digital logic implementation technology due to their small feature sizes and ultra low power consumption. Up to now, several designs using QCA technology have been proposed. However, we found not all of the designs function properly. Furthermore, no general design guidelines have been proposed so far. T...

Quantum-dot cellular automata (QCA) is an approach to computing that eliminates the need for current switches by representing binary information as the configuration of charge among quantum dots. For molecular QCA, redox sites of molecules serve as the quantum dots. The Coulomb interaction between neighboring molecules provides device–device coupling. By introducing clocked control of the QCA c...