Journal of Applied Physics

Fault tolerance calculations for clocked quantum-dot cellular automata devices

Mahfuza Khatun, Travis Barclay, Ioan Sturzu, P. Douglas Tougaw

Published Nov 1, 2005• 19 citations

Abstract

We present a numerical study of fault tolerance properties in quantum-dot cellular automata (QCA) devices. A full-basis quantum method is used for calculations of the Hamiltonian, and a statistical model has been introduced to simulate the influence of position defects of the dots within cells on the logical output. Combined effects of temperature and cell defects on a shift register have been studied. Uniform and normal distributions have been used for the cell defect simulations. Normal distribution simulations produce realistic results compared to the uniform distribution. In order to show the operational limit of a device, parameters such as “displacement factor” and “success rate” are introduced. Results show that the fault tolerance of a QCA device is strongly dependent on temperature as well as on the cell defects. The robustness of a shift register is also dependent on the size of the device.

DOI: 10.1063/1.2128473

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