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Title: Single-photon test of hyper-complex quantum theories using a metamaterial

Abstract

In standard quantum mechanics, complex numbers are used to describe the wavefunction. Although this has so far proven sufficient to predict experimental results, there is no theoretical reason to choose them over real numbers or generalizations of complex numbers, that is, hyper-complex numbers. Experiments performed to date have proven that real numbers are insufficient, but the need for hyper-complex numbers remains an open question. Here we experimentally probe hyper-complex quantum theories, studying one of their deviations from complex quantum theory: the non-commutativity of phases. We do so by passing single photons through a Sagnac interferometer containing both a metamaterial with a negative refractive index, and a positive phase shifter. In order to accomplish this we engineered a fishnet metamaterial to have a negative refractive index at 780 nm. Here, we show that the metamaterial phase commutes with other phases with high precision, allowing us to place limits on a particular prediction of hyper-complex quantum theories.

Authors:
 [1];  [1];  [2];  [3];  [2];  [2];  [4]; ORCiD logo [1]
  1. Univ. of Vienna (Austria). Vienna Center for Quantum Science and Technoloy
  2. Univ. of California, Berkeley, CA (United States). Nanoscale Science and Engineering Center; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  3. Univ. of Vienna (Austria). Vienna Center for Quantum Science and Technoloy; Univ. of Moncton, NB (Canada). Dept. of Physics and Astronomy
  4. Univ. of Vienna (Austria). Vienna Center for Quantum Science and Technoloy; Austrian Academy of Sciences, Vienna (Austria). Inst. for Quantum Optics and Quantum Information
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1411657
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; metamaterials; quantum mechanics; quantum optics; single photons and quantum effects

Citation Formats

Procopio, Lorenzo M., Rozema, Lee A., Wong, Zi Jing, Hamel, Deny R., O’Brien, Kevin, Zhang, Xiang, Dakić, Borivoje, and Walther, Philip. Single-photon test of hyper-complex quantum theories using a metamaterial. United States: N. p., 2017. Web. doi:10.1038/ncomms15044.
Procopio, Lorenzo M., Rozema, Lee A., Wong, Zi Jing, Hamel, Deny R., O’Brien, Kevin, Zhang, Xiang, Dakić, Borivoje, & Walther, Philip. Single-photon test of hyper-complex quantum theories using a metamaterial. United States. doi:10.1038/ncomms15044.
Procopio, Lorenzo M., Rozema, Lee A., Wong, Zi Jing, Hamel, Deny R., O’Brien, Kevin, Zhang, Xiang, Dakić, Borivoje, and Walther, Philip. 2017. "Single-photon test of hyper-complex quantum theories using a metamaterial". United States. doi:10.1038/ncomms15044. https://www.osti.gov/servlets/purl/1411657.
@article{osti_1411657,
title = {Single-photon test of hyper-complex quantum theories using a metamaterial},
author = {Procopio, Lorenzo M. and Rozema, Lee A. and Wong, Zi Jing and Hamel, Deny R. and O’Brien, Kevin and Zhang, Xiang and Dakić, Borivoje and Walther, Philip},
abstractNote = {In standard quantum mechanics, complex numbers are used to describe the wavefunction. Although this has so far proven sufficient to predict experimental results, there is no theoretical reason to choose them over real numbers or generalizations of complex numbers, that is, hyper-complex numbers. Experiments performed to date have proven that real numbers are insufficient, but the need for hyper-complex numbers remains an open question. Here we experimentally probe hyper-complex quantum theories, studying one of their deviations from complex quantum theory: the non-commutativity of phases. We do so by passing single photons through a Sagnac interferometer containing both a metamaterial with a negative refractive index, and a positive phase shifter. In order to accomplish this we engineered a fishnet metamaterial to have a negative refractive index at 780 nm. Here, we show that the metamaterial phase commutes with other phases with high precision, allowing us to place limits on a particular prediction of hyper-complex quantum theories.},
doi = {10.1038/ncomms15044},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = 2017,
month = 4
}

Journal Article:
Free Publicly Available Full Text
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