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arXiv · 2407.15813

Gyroscopic stability for nanoparticles in Stern-Gerlach Interferometry and spin contrast

Tian Zhou·Sougato Bose·Anupam Mazumdar
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Abstract

Creating macroscopic spatial quantum superposition with a nanoparticle has a multitude of applications, ranging from testing the foundations of quantum mechanics, matter-wave interferometer for detecting gravitational waves and probing the electromagnetic vacuum, dark matter detection and quantum sensors to testing the quantum nature of gravity in a lab. In this paper, we investigate the role of rotation in a matter-wave interferometer, where we show that imparting angular momentum along the direction of a defect, such as one present in the nitrogen-vacancy centre of a nanodiamond can cause an enhancement in spin contrast for a wide-ranging value of the angular momentum, e.g. $10^{3}-10^{6}$~Hz for a mass of order $10^{-14}-10^{-17}$ Kg nanodiamond. Furthermore, the imparted angular momentum can enhance the spatial superposition by almost a factor of two and possibly average out any potential permanent dipoles in the nanodiamond.

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Tian Zhou, Sougato Bose, Anupam Mazumdar. 2024-07-22. Gyroscopic stability for nanoparticles in Stern-Gerlach Interferometry and spin contrast. https://arxiv.org/abs/2407.15813

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