All opportunities

Offers : 37

Detection of cyber-attacks in a smart multi-sensor embedded system for soil monitoring

Mail Sélection

Start date : 1 April 2019

offer n° PsD-DRT-19-0071

The post-doc is concerned with the application of machine learning methods to detect potential cyber-security attacks on a connected multi-sensor system. The application domain is the agriculture, where CEA Leti has several projects, among which the H2020 project SARMENTI (Smart multi-sensor embedded and secure system for soil nutrient and gaseous emission monitoring). The objective of SARMENTI is to develop and validate a secure, low power multisensor systems connected to the cloud to make in situ soil nutrients analysis and to provide decision support to the farmers by monitoring soil fertility in real-time. Within this topic, the postdoc is concerned with the cyber-security analysis to determine main risks in our multi-sensor case and with the investigation of a attack detection module. The underlying detection algorithm will be based on anomaly detection, e.g., one-class classifier. The work has tree parts, implement the probes that monitor selected events, the communication infrastructure that connects the probes with the detector, and the detector itself.

  • Keywords : Engineering science, Computer science and software, Mathematics - Numerical analysis - Simulation, DACLE, Leti
  • Laboratory : DACLE / Leti
  • CEA code : PsD-DRT-19-0071
  • Contact : anca.molnos@cea.fr

Strain engineering on AlN thin films

Mail Sélection

Start date : 1 January 2019

offer n° PsD-DRT-19-0023

AlN is one of the prime material due to its outstanding piezoelectric properties for many RF and MEMS applications.

The performances of the devices strongly depend on the piezoelectric properties of the material and one promissing way to tune the properties is to set a mechanical strain to the AlN.

The goal of the post-doctoral position is to strain AlN thin film by transferring them onto various substrates. In the case of flexible polymer substrate, the strain of the polymer can stress AlN.

LETI has ever developed a process dedicated to the transfer of very thin silicon film onto a flexible substrate.

the student will be in charge of :

1/ the transfer of AlN thin onto various substrates

2/ The mechanical and electrical characterization of the transfered films

  • Keywords : Engineering science, Atomic and molecular physics, Materials and applications, DTSI, Leti
  • Laboratory : DTSI / Leti
  • CEA code : PsD-DRT-19-0023
  • Contact : pierre.montmeat@cea.fr

Frequency reference oscillators for the 5G technology based on acoustic resonators

Mail Sélection

Start date : 1 September 2019

offer n° PsD-DRT-19-0063

Millimiter-wave 5G systems require increasing modulation complexities (beyond 64 QAM) as a means to improve data bandwidth, but they are currently limited by the phase noise of local oscillators. Current reference oscillators are based on quartz resonators, limited to frequencies of few MHz. There is therefore a need for high-performance and high-frequency alternatives.

Reference oscillators based on acoustic-wave resonators represent a privileged alternative to attain good phase noise performance in the UHF band. In this context, the RF components laboratory of the CEA/Leti has a large experience in the design and fabrication of such devices, as demonstrated by its large scientific output and industrial collaborations.

The post-doc will be centred on the development of high-performance acoustic resonators in the UHF band. The objective is to optimize phase noise and temperature stability of reference oscillators, two of the main defining parameters defining their performance. The candidate will be in charge of the design, fabrication and characterization of the acoustic resonators, and the development of strategies to improve their performance.

  • Keywords : Engineering science, Electronics and microelectronics - Optoelectronics, Materials and applications, DCOS, Leti
  • Laboratory : DCOS / Leti
  • CEA code : PsD-DRT-19-0063
  • Contact : marc.sansaperna@cea.fr

Feasability study and development of models towards SPICE-simulation of silicon Qubit quantum circuits

Mail Sélection

Start date : 1 August 2019

offer n° PsD-DRT-18-0056

The Compact / SPICE model is the link between the development of technological bricks and circuit design. The model purpose is to accurately reproduce the experimental characteristics essential to digital, analog and mixed circuit design. But today we need deeper investigation to set up the specifications of models for such device, in order to provide adequate tools to help circuit designers building up quantum circuits.

The main challenge is to be able to describe the quantum behavior of this architecture. It will also be necessary to study if this behavior must be described via the physical quantities (eg electronic spin, energy level …) or by logical quantities (quantum state, matrix of transformation, …). It will also be necessary to take into account the compatibility between the mathematical formalism and the standard tools of compact modeling (through Verilog-A description).

Following recent experimental research activities (between CEA and CNRS) concerning the first demonstration of hole spin qubit on SOI, we propose first to investigate how to model such device through macro modeling approach where SET compact model, inclusion of magnetic spin degeneracy and management of RF excitation are main steps.

The challenges in regards to literature are inclusion of magnetic field in SET model, description of resonant tunneling, RF excitation of SET and reproduction of Rabi oscillations.

  • Keywords : Engineering science, Electronics and microelectronics - Optoelectronics, DCOS, Leti
  • Laboratory : DCOS / Leti
  • CEA code : PsD-DRT-18-0056
  • Contact : sebastien.martinie@cea.fr

Nano-silicon/graphene composites for high energy density lithium-ion batteries

Mail Sélection

Start date : 1 May 2018

offer n° PsD-DRF-18-0052

This postdoctoral fellowship is part of the Graphene Flagship Core 2 H2020 european project (2018-2020) on the energy storage applications of graphene. In lithium-ion batteries, graphene associated to nanostructured silicon in a proper composite helps increase the energy capacity. Indeed graphene wraps silicon, reducing its reactivity with electrolyte and the formation of the SEI passivation layer. It also maintains a high electrical conductivity within the electrode.

The study will compare two technologies: graphene-silicon nanoparticles and graphene-silicon nanowires. The former composite, already explored in the above mentioned project, will be optimized in the present study. The latter is a new kind of composite, using a large scale silicon nanowire synthesis process recently patented in the lab. The postdoc will work within two laboratories: a technological research lab (LITEN) with expertise in batteries for transportation, and a fundamental research lab (INAC) with expertise in nanomaterial synthesis.

The postdoc will synthesize silicon nanowires for his/her composites at INAC. Following LITEN know-how, she/he will be in charge of composite formulation, battery fabrication and electrochemical cycling. He/she will systematically compare the electrochemical behavior of the nanoparticle and nanowire based silicon-graphene composites. Comparison will extend to the mechanism of capacity fading and SEI formation, thanks to the characterization means available at CEA Grenoble and in the European consortium: X-ray diffraction, electronic microscopy, XPS, FTIR, NMR spectroscopies. She/he will report her/his work within the international consortium (Cambride UK, Genova Italy, Graz Austria) meetings.

A 2-year post-doctoral position is open.

PhD in materials science is requested. Experience in nanocharacterization, nanochemistry and/or electrochemistry is welcome.

Applications are expected before May 31st, 2018.

  • Keywords : Engineering science, Materials and applications, Ultra-divided matter, Physical sciences for materials, INAC, SyMMES
  • Laboratory : INAC / SyMMES
  • CEA code : PsD-DRF-18-0052
  • Contact : pascale.chenevier@cea.fr
More information
X