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A synthetic monopole source of Kalb-Ramond field in diamond

Chen, Mo and Li, Changhao and Palumbo, Giandomenico and Zhu, Yan-Qing and Goldman, Nathan and Cappellaro, Paola (2022) A synthetic monopole source of Kalb-Ramond field in diamond. Science, 375 (6584). pp. 1017-1020. ISSN 0036-8075. doi:10.1126/science.abe6437.

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Magnetic monopoles play a central role in areas of physics that range from electromagnetism to topological matter. String theory promotes conventional vector gauge fields of electrodynamics to tensor gauge fields and predicts the existence of more exotic tensor monopoles. Here, we report the synthesis of a tensor monopole in a four-dimensional parameter space defined by the spin degrees of freedom of a single solid-state defect in diamond. Using two complementary methods, we characterized the tensor monopole by measuring its quantized topological charge and its emanating Kalb-Ramond field. By introducing a fictitious external field that breaks chiral symmetry, we further observed an intriguing spectral transition, characterized by spectral rings protected by mirror symmetries. Our work demonstrates the possibility of emulating exotic topological structures inspired by string theory.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Chen, Mo0000-0002-2394-2442
Li, Changhao0000-0002-3019-5887
Palumbo, Giandomenico0000-0003-1303-1247
Zhu, Yan-Qing0000-0003-0918-6692
Goldman, Nathan0000-0002-0757-7289
Cappellaro, Paola0000-0003-3207-594X
Alternate Title:Experimental characterization of the 4D tensor monopole and topological nodal rings
Additional Information:© 2022 American Association for the Advancement of Science. Received 3 September 2020; resubmitted 16 June 2021. Accepted 14 January 2022. M.C., C.L., and P.C. thank M. Li for helpful discussions. This work is supported in part by NSF grant PHY1734011. Work in Brussels is supported by the Fonds De La Recherche Scientifique (FRS-FNRS) Belgium and the ERC Starting Grant TopoCold. Author contributions: M.C. and C.L. designed and performed the experiments and analyzed the data, with assistance from P.C. and input of N.G. on the quantum-metric measurement. M.C., C.L., and P.C. discussed and interpreted the results, ran simulations, and developed the analytical model that describes the spectral transition. M.C., C.L., and G.P. analyzed the symmetries and spectral structures of the model, with inputs from all authors. All authors contributed to the writing of the manuscript. P.C. supervised the overall project. The authors declare no conflicts of interest. Data and materials availability: The data and software code for generating the figures presented in the main text and supplementary materials are available at Harvard Dataverse (30).
Group:Institute for Quantum Information and Matter
Funding AgencyGrant Number
Fonds de la Recherche Scientifique (FNRS)UNSPECIFIED
European Research Council (ERC)716908
Issue or Number:6584
Record Number:CaltechAUTHORS:20220512-105365100
Persistent URL:
Official Citation:A synthetic monopole source of Kalb-Ramond field in diamond. Mo Chen, Changhao Li, Giandomenico Palumbo, Yan-Qing Zhu, Nathan Goldman, Paola Cappellaro. Science, 375 (6584); DOI: 10.1126/science.abe6437
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:114695
Deposited By: Tony Diaz
Deposited On:12 May 2022 16:08
Last Modified:12 May 2022 16:08

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