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arXiv · 1801.04291

Controlled-Z gate for transmon qubits coupled by semiconductor junctions

Zhenyi Qi·Hong-Yi Xie·Javad Shabani·Vladimir E. Manucharyan·Alex Levchenko·Maxim G. Vavilov
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Abstract

We analyze the coupling of two qubits via an epitaxial semiconducting junction. In particular, we consider three configurations that include pairs of transmons or gatemons as well as gatemon-like two qubits formed by an epitaxial four-terminal junction. These three configurations provide an electrical control of the interaction between the qubits by applying voltage to a metallic gate near the semiconductor junction and can be utilized to naturally realize a controlled-Z gate (CZ). We calculate the fidelity and timing for such CZ gate. We demonstrate that in the absence of decoherence, the CZ gate can be performed under $50\ {\rm ns}$ with gate error below $10^{-4}$.

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Zhenyi Qi, Hong-Yi Xie, Javad Shabani, Vladimir E. Manucharyan, Alex Levchenko, Maxim G. Vavilov. 2018-01-12. Controlled-Z gate for transmon qubits coupled by semiconductor junctions. https://doi.org/10.1103/physrevb.97.134518

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