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Simulation of a non-invasive charge detector for quantum cellular automata

G. Iannaccone·C. Ungarelli·M. Macucci·E. Amirante·M. Governale
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Abstract

Information in a Quantum Cellular Automata architecture is encoded in the polarizazion state of a cell, i.e., in the occupation numbers of the quantum dots of which the cell is made up. Non-invasive charge detectors of single electrons in a quantum dot are therefore needed, and recent experiments have shown that a quantum constriction electrostatically coupled to the quantum dot may be a viable solution. We have performed a numerical simulation of a system made of a quantum dot and a nearby quantum point contact defined, by means of depleting metal gates, in a two-dimensional electron gas at a GaAs/AlGaAs heterointerface. We have computed the occupancy of each dot and the resistance of the quantum wire as a function of the voltage applied to the plunger gate, and have derived design criteria for achieving optimal sensitivity.

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G. Iannaccone, C. Ungarelli, M. Macucci, E. Amirante, M. Governale. 1998-07-22. Simulation of a non-invasive charge detector for quantum cellular automata. https://doi.org/10.1016/s0040-6090(98)01316-9

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