Journal of Computational Electronics

, Volume 9, Issue 1, pp 16–30 | Cite as

Analysis of field-driven clocking for molecular quantum-dot cellular automata based circuits



Molecular quantum-dot cellular automaton (QCA) offers an alternative paradigm for computing at the nano-scale. QCA circuits require an external clock which can be generated using a network of submerged electrodes to synchronize information flow and provide the required power to drive the computation. In this paper, the effect of electrode separation and applied potential on the likelihood of different QCA cell states of molecular cells located above and in between two adjacent electrodes is analyzed. Using this analysis, estimates of operational ranges are developed for the placement, applied potential, and relative phase between adjacent clocking electrodes to ensure that only those states that are used in the computation are energetically favorable. Conclusions on the trade-off between cell size, cell-to-cell distance, and applied clocking potential are drawn and the temperature dependence of the operation of fundamental QCA building blocks is considered.


Clocking QCA Quantum cellular automata Power Molecular electronics 


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Copyright information

© Springer Science+Business Media LLC 2009

Authors and Affiliations

  1. 1.Department of Electrical and Computer EngineeringUniversity of British ColumbiaVancouverCanada

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