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arXiv:1907.06896 · Physical Review Research

Room temperature test of the continuous spontaneous localization model using a levitated micro-oscillator

Di Zheng, Yingchun Leng, Xi Kong, Rui Li, Zizhe Wang, Xiaohui Luo, Jie Zhao, Chang‐Kui Duan, Pu Huang, Jiangfeng Du, Matteo Carlesso, Angelo Bassi

Published Jan 17, 2020• 98 citations
arXivHTMLPDF

Abstract

The authors test the Continuous Spontaneous Localization model using a magnetically levitated micro-mechanical oscillator with ultra-high coherences. At room temperature, they obtain a new upper bound on the collapse rate improving by more than two orders of magnitude the previous results at the same working frequency.
DOI
10.1103/physrevresearch.2.013057

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The continuous spontaneous localization (CSL) model is one of the most promising approaches to address the wave function collapse problem in the measurement process of standard quantum mechanics. In this work, the effect of the CSL model on a Bragg atom interferometer was investigated. A Bragg interferometer achieving high fringe contrast of 99%\%% has been demonstrated, maintaining this performance level at interrogation time up to T=60 msT=60~\mathrm{ms}T=60 ms. The primary factors responsible for fringe contrast loss in the atom interferometer were systematically analyzed and corrected. This improvement established a new upper limit of λCSL=1.27×10−5 s−1λ_{\rm CSL}=1.27\times10^{-5}~\mathrm{s}^{-1}λCSL​=1.27×10−5 s−1 at rC=10−5 mr_C=10^{-5}~\mathrm{m}rC​=10−5 m for the CSL collapse rate, representing approximately 4 times enhancement over previous atom-interferometric constraints.
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