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arXiv · 1212.3857

Observation of Majorana Quantum Critical Behavior in a Resonant Level Coupled to a Dissipative Environment

H. T. Mebrahtu·I. V. Borzenets·H. Zheng·Y. V. Bomze·A. I. Smirnov·S. Florens·H. U. Baranger·G. Finkelstein
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Abstract

We investigate experimentally an exotic state of electronic matter obtained by fine-tuning to a quantum critical point (QCP), realized in a spin-polarized resonant level coupled to strongly dissipative electrodes. Several transport scaling laws near and far from equilibrium are measured, and then accounted for theoretically. Our analysis reveals a splitting of the resonant level into two quasi-independent Majorana modes, one strongly hybridized to the leads, and the other tightly bound to the quantum dot. Residual interactions involving these Majorana fermions result in the observation of a striking quasi-linear non-Fermi liquid scattering rate at the QCP. Our devices constitute a viable alternative to topological superconductors as a platform for studying strong correlation effects within Majorana physics.

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H. T. Mebrahtu, I. V. Borzenets, H. Zheng, Y. V. Bomze, A. I. Smirnov, S. Florens, H. U. Baranger, G. Finkelstein. 2012-12-17. Observation of Majorana Quantum Critical Behavior in a Resonant Level Coupled to a Dissipative Environment. https://doi.org/10.1038/nphys2735

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