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arXiv · 1810.07045

Matter and spin superposition in vacuum experiment (MASSIVE)

Sougato Bose·Gavin W. Morley
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Abstract

A free-falling nanodiamond containing a nitrogen vacancy centre in a spin superposition should experience a superposition of forces in an inhomogeneous magnetic field. We propose a practical design that brings the internal temperature of the diamond to under 10 K. This extends the expected spin coherence time from 2 ms to 500 ms, so the spatial superposition distance could be increased from 0.05 nm to over 1 $\mu$m, for a 1 $\mu$m diameter diamond and a magnetic inhomogeneity of only 10$^4$ T/m. The low temperature allows single-shot spin readout, reducing the number of nanodiamonds that need to be dropped by a factor of 10,000. We also propose solutions to a generic obstacle that would prevent such macroscopic superpositions.

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Sougato Bose, Gavin W. Morley. 2018-10-16. Matter and spin superposition in vacuum experiment (MASSIVE). https://arxiv.org/abs/1810.07045

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