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Reference : UPR2940-FLOPOI-028
Workplace : GRENOBLE
Date of publication : Wednesday, June 17, 2020
Type of Contract : FTC Scientist
Contract Period : 12 months
Expected date of employment : 1 October 2020
Proportion of work : Full time
Remuneration : 2648 € (monthly gross salary)
Desired level of education : 5-year university degree
Experience required : Indifferent
Graphene is a 2D material that has attracted a considerable interest since its discovery in 2005. Its gapless linear band structure that mimics massless Dirac fermions has led to the discovery of a wealth of new exciting transport properties. Moreover, the possibility to engineer very high mobility graphene devices in which electrons can travel in a ballistic fashion makes graphene the perfect playground to investigate quantum coherent phenomena in the quantum Hall regime, or when coupled with a superconducting condensate.
Our research focuses on a new topological state of matter, the quantum Hall topological insulator that our group recently discovered in graphene . This unusual quantum Hall state harbors a pair of counter-propagating, one dimensional edge channels, so-called helical edge channels, which can serve as platform to induce an unconventional superconducting state once hybridized with superconducting electrodes. One of our main objective is to study the quantum transport properties to reveal the topological nature of this proximity-induced superconductivity, that is, the presence of Majorana zero modes, in suitably designed hybrid devices. Our group has develop state-of-the-art fabrication processes of high mobility graphene devices by encapsulation of graphene monolayers between insulating boron-nitride flakes, as well as of hybrid superconducting devices.
The objective of the Postdoc project is to perform state-of-the-art low-temperature quantum transport measurement of high-mobility graphene Josephson junctions made with a high critical-field superconductors . Pioneering investigations of Josephson junctions in the quantum Hall topological insulator state, and of more advanced devices  will be performed towards coherent manipulation of Majorana bound states. The postdoc will participate in the sample fabrication, perform measurements and data analysis, and will take part in the PhD and Master students supervision.
 Helical quantum Hall phase in graphene on StrTiO3, L. Veyrat et al. Science 367, 781 (2020)
 Low temperature anomaly in disordered superconductors near Bc2 as a vortex glass properties. B. Sacépé et al. Nature Physics 48, 15 (2019)
Tunable transmission of quantum Hall edge channels in split-gated graphene devices. K. Zimmermann, et al. Nature Communications 8:14983 (2017)
We look for highly motivated candidates with a strong background in condensed matter physics / quantum physics, expertise in low-temperature transport measurement of mesoscopic devices, graphene sample fabrication and possibly time-resolved measurements of two-level systems.
The Postdoc will be part of the QuNES team, at Institut Néel, which has a strong expertise in quantum nano-electronics. The Institut NEEL is one of the largest French national research institutes for fundamental research in condensed matter physics enriched by interdisciplinary activities at the interfaces with chemistry, engineering and biology. It is located in the heart of a unique scientific, industrial and cultural environment. It is part of one of Europe's biggest high-tech environment in micro- and nanoelectronics, right next to the French Alpes.
This project will be carried out in close collaboration with theoreticians (Julia Meyer and Manuel Houzet from the CEA Grenoble) involved in the project.
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