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arXiv · 0710.3572

Theory of semiconductor quantum-wire based single- and two-qubit gates

Tobias Zibold·Peter Vogl·Andrea Bertoni
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Abstract

A GaAs/AlGaAs based two-qubit quantum device that allows the controlled generation and straightforward detection of entanglement by measuring a stationary current-voltage characteristic is proposed. We have developed a two-particle Green's function method of open systems and calculate the properties of three-dimensional interacting entangled systems non-perturbatively. We present concrete device designs and detailed, charge self-consistent predictions. One of the qubits is an all-electric Mach-Zehnder interferometer that consists of two electrostatically defined quantum wires with coupling windows, whereas the second qubit is an electrostatically defined double quantum dot located in a second two-dimensional electron gas beneath the quantum wires. We find that the entanglement of the device can be controlled externally by tuning the tunneling coupling between the two quantum dots.

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Tobias Zibold, Peter Vogl, Andrea Bertoni. 2007-10-18. Theory of semiconductor quantum-wire based single- and two-qubit gates. https://doi.org/10.1103/physrevb.76.195301

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