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arXiv · 1904.11443

Fast two-qubit logic with holes in germanium

N. W. Hendrickx·D. P. Franke·A. Sammak·G. Scappucci·M. Veldhorst
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Abstract

The promise of quantum computation with quantum dots has stimulated widespread research. Still, a platform that can combine excellent control with fast and high-fidelity operation is absent. Here, we show single and two-qubit operations based on holes in germanium. A high degree of control over the tunnel coupling and detuning is obtained by exploiting quantum wells with very low disorder and by working in a virtual gate space. Spin-orbit coupling obviates the need for microscopic elements and enables rapid qubit control with Rabi frequencies exceeding 100 MHz and a single-qubit fidelity of 99.3 %. We demonstrate fast two-qubit CX gates executed within 75 ns and minimize decoherence by operating at the charge symmetry point. Planar germanium thus matured within one year from a material that can host quantum dots to a platform enabling two-qubit logic, positioning itself as a unique material to scale up spin qubits for quantum information.

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N. W. Hendrickx, D. P. Franke, A. Sammak, G. Scappucci, M. Veldhorst. 2019-04-25. Fast two-qubit logic with holes in germanium. https://doi.org/10.1038/s41586-019-1919-3

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