QDev Seminar: Ramón Aguado – University of Copenhagen

QDev Seminar: Ramón Aguado

Parity crossings and their relation to Majorana bound state phenomenology in hybrid superconductor-semiconductor nanowire systems

Ramón Aguado, Consejo Superior de Investigaciones Científicas (CSIC), Madrid.

Recent experiments [1-5] have reported conductance measurements in semiconducting nanowire-based hybrid systems that support the existence of Majorana bound states (MBS) at normal-superconductor junctions. Although these experiments are partially consistent with the Majorana interpretation [6], other mechanisms such as disorder [7], Andreev bound states [8], or Kondo physics [9] cannot be completely ruled out. After an overview of the experimental situation, I will focus on the last two mechanisms and will explain in detail how their phenomenology mimic that of Majorana bound states. This phenomenology originates from crossings of the ground state fermionic parity.

References
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[2] M. T. Deng, C. L. Yu, G. Y. Huang, M. Larsson, P. Caroff, and H. Q. Xu, Nano Lett. 12, 6414 (2012),arXiv:1406.4435 (2014).
[3] A. Das, Y. Ronen, Y. Most, Y. Oreg, M. Heiblum, and H. Shtrikman, Nat. Phys. 8, 887 (2012).
[4] A. D. K Finck, D. J. Van Harlingen,P. K. Mohseni, K. Jung and X. Li,Phys. Rev. Lett., 110, 126406 (2013).
[5] H. O. H. Churchill, V. Fatemi, K. Grove-Rasmussen, M. T. Deng, P. Caroff, H. Q. Xu and C. M. Marcus, Phys. Rev. B, 87, 241401 (2013).
[6] E. Prada, P. San-Jose, and R. Aguado, Phys. Rev. B 86, 180503(R) (2012).
[7] J. Liu, A. C. Potter, K. T. Law, and P. A. Lee, Phys. Rev. Lett. 109, 267002 (2012).
[8] E. J. H. Lee, X. Jiang, M. Houzet, R. Aguado, C. M. Lieber, and S. De Franceschi, Nature Nanotechnology, 9, 79 (2014).
[9] E. J. H. Lee, X. Jiang, R. Aguado, G. Katsaros, C. M. Lieber, and S. De Franceschi, Phys. Rev. Lett. 109, 186802 (2012); R. Zitko, J. S. Lim, R. Lopez and R. Aguado, arXiv:1405.6084  (2014).