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arXiv · 1712.08411

Quantum Nondemolition Gate Operations and Measurements in Real Time on Fluctuating Signals

Yu Shiozawa·Jun-ichi Yoshikawa·Shota Yokoyama·Toshiyuki Kaji·Kenzo Makino·Takahiro Serikawa·Ryosuke Nakamura·Shigenari Suzuki·Shota Yamazaki·Warit Asavanant·Shuntaro Takeda·Peter van Loock·Akira Furusawa
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Abstract

We demonstrate an optical quantum nondemolition (QND) interaction gate with a bandwidth of about 100 MHz. Employing this gate, we are able to perform QND measurements in real time on randomly fluctuating signals. Our QND gate relies upon linear optics and offline-prepared squeezed states. In contrast to previous demonstrations on narrow sideband modes, our gate is compatible with non-Gaussian quantum states temporally localized in a wave-packet mode, and thus opens the way for universal gate operations and realization of quantum error correction.

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Yu Shiozawa, Jun-ichi Yoshikawa, Shota Yokoyama, Toshiyuki Kaji, Kenzo Makino, Takahiro Serikawa, Ryosuke Nakamura, Shigenari Suzuki, Shota Yamazaki, Warit Asavanant, Shuntaro Takeda, Peter van Loock, Akira Furusawa. 2017-12-22. Quantum Nondemolition Gate Operations and Measurements in Real Time on Fluctuating Signals. https://doi.org/10.1103/physreva.98.052311

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