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arXiv · 1912.03006

On-demand generation and characterization of a microwave time-bin qubit

Jesper Ilves·Shingo Kono·Yoshiki Sunada·Shota Yamazaki·Minkyu Kim·Kazuki Koshino·Yasunobu Nakamura
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Abstract

Superconducting circuits offer a scalable platform for the construction of large-scale quantum networks where information can be encoded in multiple temporal modes of propagating microwaves. Characterization of such microwave signals with a method extendable to an arbitrary number of temporal modes with a single detector and demonstration of their phase-robust nature are of great interest. Here we show the on-demand generation and Wigner tomography of a microwave time-bin qubit with superconducting circuit quantum electrodynamics architecture. We perform the tomography with a single heterodyne detector by dynamically changing the measurement quadrature with a phase-sensitive amplifier independently for the two temporal modes. By generating and measuring the qubits with hardware lacking a shared phase reference, we demonstrate conservation of phase information in each time-bin qubit generated.

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Jesper Ilves, Shingo Kono, Yoshiki Sunada, Shota Yamazaki, Minkyu Kim, Kazuki Koshino, Yasunobu Nakamura. 2019-12-06. On-demand generation and characterization of a microwave time-bin qubit. https://doi.org/10.1038/s41534-020-0266-4

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