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arXiv · 0907.2409

Microwave-Driven Transitions in Two Coupled Semiconductor Charge Qubits

K. D. Petersson·C. G. Smith·D. Anderson·P. Atkinson·G. A. C. Jones·D. A. Ritchie
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Abstract

We have studied interactions between two capacitively coupled GaAs/AlGaAs few-electron double quantum dots. Each double quantum dot defines a tunable two-level system, or qubit, in which a single excess electron occupies either the ground state of one dot or the other. Applying microwave radiation we resonantly drive transitions between states and non-invasively measure occupancy changes using proximal quantum point contact charge detectors. The level structure of the interacting two-qubit system is probed by driving it at a fixed microwave frequency whilst varying the energy detuning of both double dots. We observe additional resonant transitions consistent with a simple coupled two-qubit Hamiltonian model.

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K. D. Petersson, C. G. Smith, D. Anderson, P. Atkinson, G. A. C. Jones, D. A. Ritchie. 2009-07-14. Microwave-Driven Transitions in Two Coupled Semiconductor Charge Qubits. https://arxiv.org/abs/0907.2409

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