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Reference : UMR137-JEAGEO-002
Workplace : PALAISEAU
Date of publication : Thursday, July 30, 2020
Type of Contract : FTC Scientist
Contract Period : 12 months
Expected date of employment : 1 October 2020
Proportion of work : Full time
Remuneration : 2650 Euro brut mensuel
Desired level of education : PhD
Experience required : Indifferent
The postdoctoral research aims at empowering the combination of topological state both in real and reciprocal space through the use of Topological Materials (TM) such as Topological Insulators1 and/or Weyl semimetals2 and magnetic Skyrmions3. The objective is to develop a Skyrmion-TM based platform and realize devices with intertwined electronic-spin and topology for enhanced efficiency and new functionality that could lead to a new paradigm for ultra-dense low power nanoelectronics.
In order to leverage the potential of TIs for spin current generation and Skyrmion manipulation, we will fabricate, in the framework of SKYTOP European project and in collaboration with our partners, wafer scale epitaxial 3D TIs down to the 2D limit (such as Bi2Se3, Bi2Te3 and Sb2Te3 as well as α-Sn) using three different methodologies: MBE, (MO)CVD and sputtering. As a starting point we will study thin films of Bi2Se3 and Bi2Te3 materials which are considered to be the prototypical 3D TIs with a relatively large bulk band gap of ~0.3 eV allowing operation at room temperature. Moreover, single layer MoTe2 or WTe2, potentially RT stable 2D TI candidate, will be tried. In case of 3D TIs a particular attention will be paid to minimize the influence of the bulk states, notably by thinning down the TI films. Another way is to apply either chemical or electrostatic doping (by back gating) to bring the Fermi energy within the TI bulk band gap and near the Dirac point of the surface metallic states. The surface states will be probed by magneto-transport with a particular attention to the recent angular dependence of the magnetoresistance attributed to spin momentum locking.
A step further will be to probe the interface in between TI and ferromagnetic material. Spin pumping experiments as well as torque measurements will be performed to characterize the spin current to charge current conversion efficiency of TI material.
Structural characterizations (X-ray, AFM etc..)
Magnetic characterizations (SQUID, AGFM, Kerr etc…
Magnetotransport experiment from 4 K to Room Temperature and for fieldsranging between0 and 9T.
MThe candidates must:
- have good knowledge on nanomagnetism and spintronic
- have a good knowledge of the bibliography on chiral magnetic configurations in spintronic systems
- have good knowledge of structural technics characterization
- master standard techniques used for magnetic characterizations
- possessing know-how in nanofabrication techniques
- have a very good level of writing / speaking in English
- be able to synthesize its results and present them in public at conferences and symposiums.
- be able to work in a team
Unité Mixte de Physique CNRS Thales
1 Av Augustin Fresnel
Constraints and risks
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