Coupling a single electron to a bose–einstein condensate

ABSTRACT The coupling of electrons to matter lies at the heart of our understanding of material properties such as electrical conductivity. Electron–phonon coupling can lead to the formation

of a Cooper pair out of two repelling electrons, which forms the basis for Bardeen–Cooper–Schrieffer superconductivity1. Here we study the interaction of a single localized electron with a

Bose–Einstein condensate and show that the electron can excite phonons and eventually trigger a collective oscillation of the whole condensate. We find that the coupling is surprisingly

strong compared to that of ionic impurities, owing to the more favourable mass ratio. The electron is held in place by a single charged ionic core, forming a Rydberg bound state. This

Rydberg electron is described by a wavefunction extending to a size of up to eight micrometres, comparable to the dimensions of the condensate. In such a state, corresponding to a principal

quantum number of _n_ = 202, the Rydberg electron is interacting with several tens of thousands of condensed atoms contained within its orbit. We observe surprisingly long lifetimes and

finite size effects caused by the electron exploring the outer regions of the condensate. We anticipate future experiments on electron orbital imaging, the investigation of phonon-mediated

coupling of single electrons, and applications in quantum optics. Access through your institution Buy or subscribe This is a preview of subscription content, access via your institution

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about institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS OBSERVATION OF BOSE-EINSTEIN CONDENSATES OF EXCITONS IN A BULK

SEMICONDUCTOR Article Open access 14 September 2022 BOSONIC CONDENSATION OF EXCITON–POLARITONS IN AN ATOMICALLY THIN CRYSTAL Article 06 May 2021 ASYMMETRIC RYDBERG BLOCKADE OF GIANT EXCITONS

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Phys._ 45, 113001 (2012) Article  ADS  Google Scholar  Download references ACKNOWLEDGEMENTS We thank K. Rzążewski and J. Hecker Denschlag for discussions and C. Tresp for setting up the

Rydberg laser system. This work was funded by the Deutsche Forschungsgemeinschaft (DFG) within SFB/TRR21 and project PF 381/4-2. We also acknowledge support by the ERC under contract number

267100, and A.G. acknowledges support from EU Marie Curie programme ITN-Coherence 265031. S.H. is supported by the DFG through project HO 4787/1-1. AUTHOR INFORMATION AUTHORS AND

AFFILIATIONS * 5. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany , Jonathan B. Balewski, Alexander T. Krupp, Anita Gaj, Robert Löw, Sebastian

Hofferberth & Tilman Pfau * Institut für Theoretische Physik III, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany , David Peter & Hans Peter Büchler Authors *

Jonathan B. Balewski View author publications You can also search for this author inPubMed Google Scholar * Alexander T. Krupp View author publications You can also search for this author

inPubMed Google Scholar * Anita Gaj View author publications You can also search for this author inPubMed Google Scholar * David Peter View author publications You can also search for this

author inPubMed Google Scholar * Hans Peter Büchler View author publications You can also search for this author inPubMed Google Scholar * Robert Löw View author publications You can also

search for this author inPubMed Google Scholar * Sebastian Hofferberth View author publications You can also search for this author inPubMed Google Scholar * Tilman Pfau View author

publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS The experiment was conceived by J.B.B., R.L., S.H. and T.P. and carried out by J.B.B., A.T.K. and A.G.;

data analysis was accomplished by J.B.B., A.T.K. and A.G.; perturbation theory was developed by D.P. and H.P.B.; and J.B.B. and D.P. wrote the manuscript with contributions from all

authors. CORRESPONDING AUTHOR Correspondence to Tilman Pfau. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing financial interests. SUPPLEMENTARY INFORMATION

SUPPLEMENTARY INFORMATION This file contains Supplementary Text and Data, which includes a Supplementary Discussion, Supplementary Figures 1-2 and additional references. (PDF 214 kb)

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Balewski, J., Krupp, A., Gaj, A. _et al._ Coupling a single electron to a Bose–Einstein condensate. _Nature_ 502, 664–667 (2013). https://doi.org/10.1038/nature12592 Download citation *

Received: 06 June 2013 * Accepted: 20 August 2013 * Published: 30 October 2013 * Issue Date: 31 October 2013 * DOI: https://doi.org/10.1038/nature12592 SHARE THIS ARTICLE Anyone you share

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