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arXiv · 1603.01553

On-chip quantum interference of a superconducting microsphere

H. Pino·J. Prat-Camps·K. Sinha·B. P. Venkatesh·O. Romero-Isart
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Abstract

We propose and analyze an all-magnetic scheme to perform a Young's double slit experiment with a micron-sized superconducting sphere of mass $\gtrsim {10}^{13}$ amu. We show that its center of mass could be prepared in a spatial quantum superposition state with an extent of the order of half a micrometer. The scheme is based on magnetically levitating the sphere above a superconducting chip and letting it skate through a static magnetic potential landscape where it interacts for short intervals with quantum circuits. In this way, a protocol for fast quantum interferometry using quantum magnetomechanics is passively implemented. Such a table-top earth-based quantum experiment would operate in a parameter regime where gravitational energy scales become relevant. In particular, we show that the faint parameter-free gravitationally-induced decoherence collapse model, proposed by Diósi and Penrose, could be unambiguously falsified.

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H. Pino, J. Prat-Camps, K. Sinha, B. P. Venkatesh, O. Romero-Isart. 2018-01-25. On-chip quantum interference of a superconducting microsphere. https://doi.org/10.1088/2058-9565%2Faa9d15

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