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arXiv · 1608.04908

A two-fold quantum delayed-choice experiment in a superconducting circuit

K. Liu·Y. Xu·W. Wang·Shi-Biao Zheng·Tanay Roy·Suman Kundu·Madhavi Chand·A. Ranadive·R. Vijay·Y. P. Song·L. -M. Duan·L. Sun
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Abstract

We propose and experimentally demonstrate a two-fold quantum delayed-choice experiment where wave or particle nature of a superconducting interfering device can be post-selected twice after the interferometer. The wave-particle complementarity is controlled by a quantum which-path detector (WPD) in a superposition of its on and off states implemented through a superconducting cavity. The WPD projected to its on state records which-path information, which manifests the particle nature and destroys the interference associated with wave nature of the system. In our experiment, we can recover the interference signal through a quantum eraser even if the WPD has selected out the particle nature in the first round of delayed-choice detection, showing that a quantum WPD adds further unprecedented controllability to test of wave-particle complementarity through the peculiar quantum delayed-choice measurements.

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K. Liu, Y. Xu, W. Wang, Shi-Biao Zheng, Tanay Roy, Suman Kundu, Madhavi Chand, A. Ranadive, R. Vijay, Y. P. Song, L. -M. Duan, L. Sun. 2016-08-17. A two-fold quantum delayed-choice experiment in a superconducting circuit. https://doi.org/10.1126/sciadv.1603159

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