Ballistic Single-Electron Quputer

Radu Ionicioiu; Gehan Amaratunga; Florin Udrea

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Ballistic Single-Electron Quputer

Radu Ionicioiu·Gehan Amaratunga·Florin Udrea

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Abstract

We propose a new solid state implementation of a quantum computer (quputer) using ballistic single electrons as flying qubits in 1D nanowires. We use a single electron pump (SEP) to prepare the initial state and a single electron transistor (SET) to measure the final state. Single qubit gates are implemented using quantum dots as phase shifters and electron waveguide couplers as beam splitters. A Coulomb coupler acts as a 2-qubit gate, using a mutual phase modulation effect. Since the electron phase coherence length in GaAs/AlGaAs heterostructures is of the order of 30$μ$m, several gates (tens) can be implemented before the system decoheres.

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Radu Ionicioiu, Gehan Amaratunga, Florin Udrea. 1999-07-11. Ballistic Single-Electron Quputer. https://arxiv.org/abs/quant-ph/9907043

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