Display options
Cite
Albrecht SM, Higginbotham AP, Madsen M, et al. Exponential protection of zero modes in Majorana islands. Nature. 2016;531(7593):206-9doi: 10.1038/nature17162.
Albrecht, S. M., Higginbotham, A. P., Madsen, M., Kuemmeth, F., Jespersen, T. S., Nygård, J., Krogstrup, P., & Marcus, C. M. (2016). Exponential protection of zero modes in Majorana islands. Nature, 531(7593), 206-9. https://doi.org/10.1038/nature17162
Albrecht, S M, et al. "Exponential protection of zero modes in Majorana islands." Nature vol. 531,7593 (2016): 206-9. doi: https://doi.org/10.1038/nature17162
Albrecht SM, Higginbotham AP, Madsen M, Kuemmeth F, Jespersen TS, Nygård J, Krogstrup P, Marcus CM. Exponential protection of zero modes in Majorana islands. Nature. 2016 Mar 10;531(7593):206-9. doi: 10.1038/nature17162. PMID: 26961654.
Copy Download .nbib Format: NLM
Share it on

Nature. 2016 Mar 10;531(7593):206-9. doi: 10.1038/nature17162.

Exponential protection of zero modes in Majorana islands.

Nature

S M Albrecht, A P Higginbotham, M Madsen, F Kuemmeth, T S Jespersen, J Nygård, P Krogstrup, C M Marcus

Affiliations

  1. Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
  2. Department of Physics, Harvard University, Cambridge, Massachusetts, USA.

PMID: 26961654 DOI: 10.1038/nature17162

Abstract

Majorana zero modes are quasiparticle excitations in condensed matter systems that have been proposed as building blocks of fault-tolerant quantum computers. They are expected to exhibit non-Abelian particle statistics, in contrast to the usual statistics of fermions and bosons, enabling quantum operations to be performed by braiding isolated modes around one another. Quantum braiding operations are topologically protected insofar as these modes are pinned near zero energy, with the departure from zero expected to be exponentially small as the modes become spatially separated. Following theoretical proposals, several experiments have identified signatures of Majorana modes in nanowires with proximity-induced superconductivity and atomic chains, with small amounts of mode splitting potentially explained by hybridization of Majorana modes. Here, we use Coulomb-blockade spectroscopy in an InAs nanowire segment with epitaxial aluminium, which forms a proximity-induced superconducting Coulomb island (a 'Majorana island') that is isolated from normal-metal leads by tunnel barriers, to measure the splitting of near-zero-energy Majorana modes. We observe exponential suppression of energy splitting with increasing wire length. For short devices of a few hundred nanometres, sub-gap state energies oscillate as the magnetic field is varied, as is expected for hybridized Majorana modes. Splitting decreases by a factor of about ten for each half a micrometre of increased wire length. For devices longer than about one micrometre, transport in strong magnetic fields occurs through a zero-energy state that is energetically isolated from a continuum, yielding uniformly spaced Coulomb-blockade conductance peaks, consistent with teleportation via Majorana modes. Our results help to explain the trivial-to-topological transition in finite systems and to quantify the scaling of topological protection with end-mode separation.

References

  1. Nano Lett. 2012 Dec 12;12(12):6414-9 - PubMed
  2. Science. 2014 Oct 31;346(6209):602-7 - PubMed
  3. Phys Rev Lett. 2010 Oct 22;105(17):177002 - PubMed
  4. Science. 2012 May 25;336(6084):1003-7 - PubMed
  5. Phys Rev Lett. 2010 Feb 5;104(5):056402 - PubMed
  6. Phys Rev Lett. 1994 Mar 14;72(11):1742-1745 - PubMed
  7. Phys Rev Lett. 2007 Jun 29;98(26):266801 - PubMed
  8. Nat Mater. 2015 Apr;14(4):400-6 - PubMed
  9. Phys Rev Lett. 2011 Oct 21;107(17):176811 - PubMed
  10. Phys Rev Lett. 1993 Mar 22;70(12):1862-1865 - PubMed
  11. Phys Rev Lett. 1993 Feb 15;70(7):994-997 - PubMed
  12. Phys Rev Lett. 2010 Aug 13;105(7):077001 - PubMed
  13. Nano Lett. 2008 Nov;8(11):3932-5 - PubMed
  14. Phys Rev Lett. 1992 Sep 28;69(13):1997-2000 - PubMed
  15. Phys Rev Lett. 2012 Oct 19;109(16):166403 - PubMed
  16. Phys Rev Lett. 1993 Jun 28;70(26):4138-4141 - PubMed

Publication Types