All opportunities

Thesis offer
Multi-feed reconfigurable antenna system using bio-sourced
substrate for the sub-7 GHz 5G and beyond

Context and objective:
The ICT sector contributed to about 3% of the worldwide CO2 emissions and this percentage is increasing with the increase in communication needs [1]. To meet the requirements of a high data rate communication system as well as low environmental impact, the PERSEUS project has been initiated in the frame of the PEPR-5G program.
This project aims at developing the sub-7 GHz (700 MHz – 7 GHz) for an energy-efficient and eco-friendly system.

Several approaches could be considered to reach this objective including the well-known 3Rs: “reduce, reuse, and recycle”. The bio-sourced materials [2] (e.g., paper [3]–[7], nano-cellulose conductive ink [7], plant-derived PLA (polylactic acid) [8]) could be used to reduce the need for fossil and rare resources. At the end of the life cycle, the bio-sourced materials could be recycled or decomposed to reduce the environmental impacts. The reconfigurable or modular systems could also be considered for sustainable electronics.

In this context, the DHREAMS team from the IMEP-LaHC laboratory (UMR 5130) aims at developing a multi-feed reconfigurable antenna system using bio-sourced substrate.
The multi-feed allows at the same time the modification of incident signal to change the antenna behaviors (frequency and radiation) and the integration of distributed amplifiers to increase the power efficiency [9]-[11]. To further reduce the losses in powercombining, the multi-function antenna will be considered to “remove” the matching network between the antenna and active components (UNICA) [12].

Workplan :
In order to fulfill our objectives, the Ph.D. candidate has to realize the following tasks:

➢ Literature review on the existing bio-sourced substrate in considering their physical (RF, mechanical, thermal) properties.
➢ Propose one or several potential bio-sourced substrates that could be used to develop the sub-7 GHz 5G systems.
➢ Complete this literature review by considering the reconfigurable (and) multi-feed antenna.
➢ Design and characterize some conventional antennas (with one feeding source) using the selected bio-sourced substrate(s) to identify and minimize the sources of error and to master the fabrication process.
➢ Design and characterize multi-feed antenna using selected bio-sourced substrate to evaluate the power handing capability in considering the integration with electronics components for reconfigurability.
➢ Design and characterize multi-feed reconfigurable antenna using selected bio-sourced substrate.
➢ Design and characterize active antenna with a distributed network of amplifiers using the UNICA concept.

Profile:

➢ Education level: Master 2R or Engineer in RF and electronics.
➢ Competences:
• Knowledge in electromagnetism, antenna, and RF components is required.
• Knowledge in electromagnetism simulation tools (e.g., CST, HFSS, ADS) and the RF measurement equipment (e.g., VNA, spectrum analyzer) will be appreciated.
• Fluency in English will be appreciated.
➢ Experiences: an experience (internship, study project, …) in the RF domain is expected.
➢ Being motivated in sustainable electronics is a plus.

Laboratory:
The Ph.D. candidate will join the DHREAMS team from the IMEP-LaHC laboratory (UMR 5130), 03 Parvis Louis Néel, 38016 Grenoble Cedex 1.

Supervisors:
Pr. Pascal XAVIER
Pr. Tan Phu VUONG
MCF. Nhu Huan NGUYEN

How to apply:
Please send us your CV and motivation letter BEFORE 12 MAY 2023.

Registration and financial support:
The Ph.D. candidate will have to register at the doctoral school EEATS and will receive financial support of about 2044.12€ / month (BRUT).

References:
[1] J. Malmodin and D. Lundén, “The Energy and Carbon Footprint of the Global ICT and E&M Sectors 2010–2015,” Sustainability, vol. 10, no. 9, p. 3027, Aug. 2018, doi: 10.3390/su10093027.

[2] https://www.ecologie.gouv.fr/materiaux-construction-biosources-et-geosources

[3] Ines Kharrat. Modélisation et réalisation d’un système de récupération d’énergie imprimé : caractérisation hyperfréquence des matériaux papiers utilisés. Optique / photonique. Université de Grenoble, 2014. Français. ffNNT : 2014GRENT106ff. fftel-01314122.

[4] Do Hanh Ngan Bui. Printed flexible antenna for energy harvesting. Optics / Photonic. Université Grenoble Alpes, 2017. English. ffNNT : 2017GREAT062ff. fftel-01721461f.

[5] Hong Phuong Phan. Design of 2D and 3D antennas on flexible materials. Optics / Photonic. Université Grenoble Alpes, 2018. English. ffNNT : 2018GREAT106ff. fftel-021388.

[6] Erika Vandelle. Exploration of antenna and passive beamforming techniques for wireless energy harvesting and transfer. Optics / Photonic. Université Grenoble Alpes, 2019. English. NNT : 2019GREAT060. tel-02905411.

[7] Maxime Wawrzyniak. Development of innovative and transparent radio frequency devices based on nanocelluloses silver nanowires hybrid system. Université Grenoble Alpes, soutenue en 2022.

[8] P. Xavier, G. Zakka El Nashef, E. Perrin, F. Jestin, D. Rauly, N. Corrao, et N. Chevalier, “Dispositifs hyperfréquences à faible impact environnemental,” Journées Nationales Microondes (JNM), Limoges, France, Juin 2022.

[9] S. Li, T. Chi, J. S. Park and H. Wang, “A multi-feed antenna for antenna-level power combining,” 2016 IEEE International Symposium on Antennas and Propagation (APSURSI), Fajardo, PR, USA, 2016, pp. 1589-1590, doi: 10.1109/APS.2016.7696501.

[10] H. Wang et al., “Towards Energy-Efficient 5G Mm-Wave links: Exploiting broadband Mm-Wave doherty power amplifier and multi-feed antenna with direct on-antenna power combining,” 2017 IEEE Bipolar/BiCMOS Circuits and Technology Meeting (BCTM), Miami, FL, USA, 2017, pp. 30-37,
doi: 10.1109/BCTM.2017.8112905.

[11] S. Li, T. Chi and H. Wang, “Multi-Feed Antenna and Electronics Co-Design: An E-Band Antenna- LNA Front End With On-Antenna Noise-Canceling and G
ₘ-Boosting,” in IEEE Journal of Solid- State Circuits, vol. 55, no. 12, pp. 3362-3375, Dec. 2020, doi: 10.1109/JSSC.2020.3024592.

[12] S. N. Nallandhigal and K. Wu, “Unified and Integrated Circuit Antenna in Front End—A Proof of Concept,” in IEEE Transactions on Microwave Theory and Techniques, vol. 67, no. 1, pp. 347-364, Jan. 2019, doi: 10.1109/TMTT.2018.2872962.

• Keywords : Engineering sciences, Electronics and microelectronics - Optoelectronics, FMNT, IMEP-LaHc
• Laboratory : FMNT / IMEP-LaHc
• CEA code : IMEPLAHC-DHREAMS-04-18-2023
• Contact : nhu-huan.nguyen@grenoble-inp.fr

PhD position
Integrated Photonic on glass for THz Frequency Generation

The thesis will focus on the development of co-integrated Glass DFB Lasers for THz generation and  the demonstration to high speed communications. Several advanced applications, such as next wireless  communication system (6G and beyond), spectroscopes and radars require high purity radio frequency  signals. These lasts are more and more difficult to generate as the signal frequency increases using  conventional electrical techniques. Solutions based on heterodyning of optical sources have  demonstrated to be the preferred way to produce frequencies higher than 100GHz (aka THz  frequencies).
We already demonstrated the potential of the ion exchanges platform for the generation of 300GHz communication signals, y integrating several lasers in a single glass chip. The intrinsic coherence of  those lasers, several orders of magnitude better than those based on other integrated technologies allow implementing advanced modulation formats such as QAM and OFDM to further improve the  transmission capabilities of THz communication systems.

The objective of this PhD is to enhance the performances our integrated glass chips to reach frequency  up to 600GHz. Different solutions have already been identified, like integrating distinct Bragg gratings in a single glass chip for example. The laser stability will also be improved through the insertion of
phase shifts in laser cavities.
Another objective is to integrate specific technologies to enhance the module: we will associate two  different chips in a single module for specific functions. One module will be dedicated to the laser  sources, and another module will consist of advanced Lithium Niobate modulators dedicated to optical  coherent communications. The multi-chip module will be integrated in a compact package, interfaced  with optical fibres and electrical DC and RF ports.
In order to qualify the modules and demonstrate their potential for high demanding applications such  as telecommunication, advanced characterization will be implemented. As an example, both spectral  and time domain characterisation will be analysed to study the laser frequency noise dynamic and  noise transfer to the THz signal during the heterodyning process. Detailed studies based on frequency  Allan variance will be used to qualify and determine the different contributions to laser linewidth.
Finally, the chips will be inserted in communication links using advanced modulation formats to  demonstrate the capabilities of the ion exchange platform for THz communications.

The PhD work will benefit from worldwide recognized know-how and facilities of the IMEP-LAHC  laboratory, including clean rooms access, and advanced characterizations set-ups. Some aspects of the  work will benefit from existing collaborations, for modulator chip, for advanced THz characterizations
and system demonstrations.

As the applicant will work in an interactive team and will be in direct contact with industrial and  academic partners, we are looking for someone willing to work in a collaborative environment. The  work requires experimental fabrication, characterization and analysis, but also strong theoretical  knowledge to understand the origin of the system perturbations and their impacts on the final  application. Consequently, we are looking for candidates having susceptibility for experimental work,  and strong will to develop their theoretical backgrounds in the following fields:
Laser Physics, High speed optical systems, Noise analysis.

Starting date: Oct. 2023
For more details, please contact:
Julien POËTTE julien.poette@grenoble-inp.fr
Lionel BASTARD lionel.bastard@grenoble-inp.fr
Jean-Emmanuel BROQUIN jean-emmanuel.broquin@grenoble-inp.fr

• Keywords : Engineering sciences, Electronics and microelectronics - Optoelectronics, Electronics and microelectronics - Optoelectronics, IMEP-LaHc, LMGP
• Laboratory : IMEP-LaHc / LMGP
• CEA code : IMEPLAHC-PHOTO-04-18-2023
• Contact : julien.poette@grenoble-inp.fr

PhD position 2023-2024
Development of methods for characterization and modeling of complex media in the THz domain

1- Context and scientific issues
The terahertz (THz) domain is very promising for the detection of substances and materials [1], for security purposes [2], for non-destructive testing [3] but also for very high speed telecommunications (5 and 6G).
Thus, in these applications, as for example and more precisely for the construction of very high speed telecommunication systems involving frequencies in the millimeter range and above, it is necessary to have a perfect knowledge of the media in which the waves propagate and with which they are brought to interact.
Many materials have already been characterized and their characteristics (refractive index, absorption or otherwise considered dielectric permittivity) are now known on the spectral band of interest which typically ranges between 100 GHz and several THz. For example, common dielectric materials (paper, fabrics,
plastics…) are transparent to these waves [4].
However, the materials constituting the transmission channel are very often far from ideal, they can contain a variable moisture rate and they are mostly heterogeneous in composition and/or structure: mixtures of different materials, possibly structured (multilayered, porous, more or less rough), etc. It is therefore
necessary to take this complex structure into account this complex structure in the methods used to characterize them as well as in the model to predict their behavior. In fine, in fine, these studies will lead to the modeling of the entire transmission channel in order to optimize its performance, limits…

The objectives of the project are therefore:

• to develop characterization methods specifically adapted to the complex materials of interest,
• to characterize these materials under different temperature and humidity conditions and over a wide spectral range from sub-THz to several THz,
• to propose theoretical models of these heterogeneous materials (scattering models [5], effective medium models [6], diffraction models [7]…),
  In addition, always with the aim of developing new methods of characterization, it will be necessary to implement an experiment of type optical pump – THz probe to study the dynamic and/or nonlinear properties [11] of certain materials which can be used to manufacture devices of emission and detection of THz wave, or of shaping of THz beams.

The IMEP-LAHC laboratory is internationally recognized for its activities in the field of THz characterization of materials and devices developed since the 1990s [8-10]. The project will rely on the THz characterization facilities of the PLATERA platform of the IMEP-LAHC laboratory  and on its competences in terms of development of characterization methods for materials and devices. More precisely, the Platera platform has the following systems: 2 THz-TDS spectrometers (Time Domain Spectroscopy) and imaging systems, 1 CW (Continuous Waves) spectrometer, 1 multispectral “video rate” imaging system based
on an electronic multiplication chain (82 GHz- 1. 1 THz) associated with a THz camera, a THz optical pump- probe experiment using an amplified femtosecond laser and an OPA (Optical Parametric Amplifier) allowing to tune the wavelength of the optical pump beam between 280 nm and 2μm [11].

2- Goals and methods
The objective is to characterize the “optical” properties of samples heterogeneous in composition and structure, i.e. made of materials of different natures that can be mixtures, laminar structures, porous, more or less rough etc. …. The extraction of the properties of these complex materials (absorbing, scattering,
dispersive) which constitute the environment of the transmission channel require the development of adapted measurement protocols, the modeling of coupled phenomena (absorption, diffusion etc…) and the deployment of a numerical solution allowing to obtain the properties of materials of the mixture from the
measurements.
We will also be interested in the effects of humidity, especially for porous materials found in buildings such as construction materials and thermal and sound insulation (gypsum boards, wood boards – OSB, glass wool, wood wool etc.).
Beyond the materials constituting the transmission channel, it will also be necessary to characterize certain materials constituting the transmitters and receivers or certain passive components used in a transmission system such as lenses, filters etc…

The thesis work will therefore include 6 main tasks:
– Task 1: Sub-THz and THz characterization benches
In the context of the study, it is necessary to acquire an atmospheric chamber allowing to control the humidity rate on an important range (0% -> 90%) and if necessary, the temperature of the sample. It will be necessary to install/construct this chamber on the basis of already operational experiments (TDS
Spectrometers).

– Task 2: Effective media – mixtures
For materials composed of mixtures whose constituent elements or inclusions exhibit dimensions much smaller than the considered wavelength, it will be necessary to validate the possibility of using effective media models. For hydrophilic or porous materials, elements such as water and air will have to be
systematically taken into account.

– Task 3: Diffusing media
As soon as the aggregates or inclusions are sufficiently large compared to the wavelengths, the use of scattering models will be necessary to predict the behavior of materials, particularly in terms of losses. Thus,
it will be necessary to validate the type of scattering phenomena (Mie, Rayleigh…) involved and this the most
appropriate model.

– Task 4: Diffractive media
Sometimes, structured materials possibly periodically may be encountered (fabrics for example [7]), we had to verify the occurrence of diffraction phenomena and for the simplest structures (1D) to verify the validity of “standard” models, or if needed to use numerical methods (Finite Elements) for 2D/3D structures.

– Task 5: Study in real conditions
In addition, and transversally to the previous tasks, it will be necessary to study the effects of humidity andeven temperature on the behavior of materials of interest. In particular, the humidity rate should a priori be one of the most important parameters; the materials will thus be studied over a wide range of humidity rates from a few % to more than 90%.

– Task 6: Characterization of dynamic and non-linear properties of materials
In addition, still with the aim of developing new methods of characterization, we propose to implement an experiment of the type optical pump – THz probe [11] which will make it possible to characterize the dynamic effects in certain semiconductor or nonlinear materials possibly usable in devices of emission and detectionor shaping of the THz beams.

3- References
[1] R. Miles, X.-C. Zhang, H. Eisele, A. Krotkus, « Terahertz Frequency Detection and Identification of Materials and Objects », NATO Science for Peace and Security Series B: Physics and Biophysics, Springer Nature (2021)
[2] A.U. Sokolnikov, « THz Identification for Defense and Security Purposes », World Scientific (2013
[3] D. Nüßler, J. Jonuscheit, « Terahertz based non-destructive testing (NDT) – Making the invisible visible », Oldenbourg Wissenschaftsverlag April 7 (2020) – DOI 10.1515/teme-2019-0100
[4] E. Hérault, F. Garet, J.-L. Coutaz, “On the possibility of identifying substances by remote active THz spectroscopy”, IEEE Transactions on Terahertz Science and Technology, 6, 1, 12-19 (january 2016)
[5] F. Garet, M. Hofman, J. Meilhan, F. Simoens, J.-L. Coutaz, “Evidence of Mie scattering at terahertz frequencies inpowder materials”, App. Phys. Lett., 105 (3), 031106 (2014) – doi: 10.1063/1.4890732.
[6] M. Scheller, S. Wietzke, C. Jansen, and M. Koch, ‘Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory’, J. Phys. Appl. Phys., vol. 42, no. 6, 2009
[7] Emilie Hérault, Maxence Hofman, F. Garet and Jean-Louis Coutaz, “Observation of terahertz beam diffraction byfabrics”, Opt. Lett., 38, 15, (sept. 2013) – 10.1063/1.4821627.
[8] L. Duvillaret, F. Garet, J.L. Coutaz, “A Reliable method for extraction of Material Parameters in THz Time-DomainSpectroscopy”, IEEE JSTQE, 2, pp. 739-746 (1996) – citations  1000.
[9] M. Bernier, F. Garet, J.-L. Coutaz, H. Minamide, A. Sato, “Accurate Characterization of Resonant Samples in theTerahertz Regime Through a Technique Combining Time-Domain Spectroscopy and Kramers–Kronig Analysis”, IEEETransactions on Terahertz Science and Technology, Volume: 6, Issue: 3, May 2016
[10] Coutaz J. –L. Garet F., and V. P. Wallace, « Principles of Terahertz Time-domain Spectroscopy ». Ed. Pan Stanford Publishing, (décembre 2018) – ISBN 9789814774567
[11] D. Zhai, E. Hérault, F. Garet, J.-L. Coutaz, Ci-Ling Pan “THz generation in GaSe crystals pumped with laser photonenergy below and around the bandgap“, Appl. Phys. Lett. 122, 011103 (2023); https://doi.org/10.1063/5.0128292

3- Candidates requirements
– Education level: Master or equivalent degree in electrical or material engineering or physics.
– Expertise: Microwave engineering, Physics of semiconductors, Numerical modeling (HFSS), Instrumentation
are appreciated.
Language: English, French (not required).

4- Other information
– PhD. duration: 36 months.
– Gross Salary: 2200 € /month (up to 2400 € including teaching possibility up to 64h/year)
– Benefits: French social security system, funding for conferences, access to the laboratory and its large instrumentation hardware resources (https://www.platera.tech/)
Location: IMEP-LAHC Laboratory, University Savoie Mont-Blanc, Rue Lac de la Thuiles, 73370 Le Bourget du
Lac
Contact: Frederic GARET – garet@univ-smb.fr

• Keywords : FMNT, IMEP-LaHc
• Laboratory : FMNT / IMEP-LaHc
• CEA code : IMEPLAHC-PHOTO-04-14-2023
• Contact : frederic.garet@univ-smb.fr

Thesis topic
Title : Design and realization of a complete bio‑sourced RF transmitter chain

Mots-clés :
Electronique durable, Hyperfréquences, Electromagnétisme, Antenne active, Analyse de cycle de vie.

Contexte :
CISTEME, Centre de Resource Technique (CRT) spécialisé dans l’électronique RF et télécommunications, s’est positionné, depuis quelque temps, comme un acteur de la transition écologique dans son domaine d’expertise sur le thème de l’écoconception électronique et en particulier la conception des systèmes RF offrant les mêmes services et performances mais avec des impacts environnementaux beaucoup plus faibles, à la fois sur le plan du bilan carbone mais aussi sur le plan des consommations de matériaux [1-4].
En tant que doctorant, vous intégrerez nos équipes pour travailler sur la partie écoconception et réalisation d’une chaine complète de transmission RF sur substrat biosourcé incluant mélangeur, filtre, amplificateur, antennes. L’un des enjeux est de comparer ses performances avec le même système réalisé de manière classique, notamment en matière de consommation d’énergie et d’encombrement. Ces deux derniers points sont des enjeux critiques dans le domaine de
l’électronique durable où la consommation et le coût sont des éléments-clés du point de vue du déploiement. Un autre enjeu majeur est de définir les matériaux bio-sourcés susceptibles d’être utilisés dans la bande de fréquences désirée, pour optimiser et intégrer le système antennaire actif.

Objectifs :
Le travail de thèse portera sur la définition, la conception et la réalisation de deux chaines de transmissions RF. La première sera réalisée sur des matériaux classiques, par exemple le RO4003C. La deuxième sera réalisée sur des matériaux biosourcés (à définir). Le doctorantdevra rechercher les substrats RF écologiques disponibles sur le marché et évaluer leur degré de maturité technologique en tenant compte des contraintes liées à leurs possibilités de
métallisation et des procédés nécessaires au tirage du circuit. La chaine TX à concevoir sur des matériaux biosourcés abordera le problème de la tenue mécanique, tenue en puissance et sa performance électromagnétique afin d’étudier sa faisabilité selon des spécifications opérationnelles. L’objectif général est de faire un benchmark des technologies PCB (Printed Circuit Board) écologiques pour les circuits hyperfréquences passifs et actifs, ainsi qu’un
comparatif des performances obtenues pour les mêmes circuits réalisés sur différents substrats, classiques ou écologiques, tenant compte à la fois des contributions respectives du substrat, de la métallisation et des procédés de fabrication.

•  Les principales tâches durant cette thèse sont :
  • Modélisation avancée pour les deux chaines de transmission, la conception des filtres, des amplificateurs et des antennes sur deux substrats différents et la mesure de deux prototypes.
  • Caractérisation RF dans la bande de fonctionnement pour les différents matériaux écologiques choisis afin de connaître les propriétés diélectriques des substrats en termes de constante diélectrique et de tangente de pertes. Choisir le meilleur substrat pour notre application.
  • Evaluer les performances des deux chaines visant à optimiser la performance globale du système rayonnant en traitant les problèmes de matériaux biosourcés avec la présence des dispositifs actifs, en fonction des caractéristiques diélectriques et mécaniques du matériau et de la bande de fréquence.
  • Minimiser l’encombrement du système, tout en tenant compte des contraintes liées à l’interface entre la partie rayonnante et le réseau d’alimentation (filtre + ampli). L’objectif sera de viser à réduire et à optimiser sa consommation énergétique.
  • Définir les règles à respecter pendant la conception et la réalisation des chaines RF sur des substrats biosourcés.
  • Après avoir réalisé et mesuré les deux chaines, une analyse de cycle de vie utilisant le logiciel Bilan Produit de l’ADEME sera effectuée pour évaluer les impacts environnementaux des deux chaines de transmission fabriquées. Le doctorant ou la doctorante pourra ainsi en déduire un « facteur de mérite» correspondant au quotient des performances sur les impacts environnementaux.
•  Pour mener à bien cette thèse, le plan de travail prévisionnel se décompose comme suit :
  • Phase 1 : Etude bibliographique ayant pour objectif de faire un état des lieux des principales architectures de la littérature avec leurs avantages et inconvénients par rapport à la mission visée. En particulier, les substrats biosourcés éligibles pour cette étude seront étudiées en détail, notamment la sensibilité des caractéristiques diélectriques en fonction de la température, l’humidité et de la fréquence.
  • Phase 2 : Prise en main des principales méthodes et outils numériques nécessaires à la conception conjointe et caractérisation d’une chaîne de transmission.
  •  Phase 3 : Définition d’un substrat biosourcé compatible pour l’application et étude de sa mise en place. Au cours de cette étape, une autre chaine sera désignée et réalisée sur un substrat classique. Les différents paramètres électromagnétiques (coefficient de réflexion, diagramme de rayonnement, lobes secondaires, etc.) seront analysés sur les bandes de fréquences ciblées. Une étape expérimentale de validation des deux choix
    technologiques (Biosourcé Vs Classique) sera réalisée.
  • Phase 4 : Analyse prospective des performances et des prérequis des éléments nécessaires à la définition d’un système de transmission RF sur substrat biosourcé. Il s’agira de lister les principales solutions disponibles dans les bandes de fréquences d’intérêt, et de définir, le cas échéant, les principales caractéristiques d’une conception spécifique le cas échéant.
  • Phase 5 : rédaction du manuscrit de thèse et valorisation du travail.

PROFIL RECHERCHE

• Master 2 dans le domaine de l’électronique et les hyperfréquences. Des connaissances de base sur les antennes et de l’électromagnétisme avec une petite expérience (stage) dans la conception de réseaux d’antennes et la technologie frontale RF seront appréciées.
• Connaissance des outils de simulation pour EM : CST MWS, Keysight ADS et Matlab.
• Maîtrise de l’anglais pour les conférences et la communication sera également appréciée.

SUPERVISEUR :
Pour postuler, veuillez envoyer une lettre de motivation, un CV détaillé et des références académiques à :

• Georges ZAKKA EL NASHEF, elnashef@cisteme.net
  Lieu : Centre d’Ingénierie des Systèmes en Télécommunications en ElectroMagnétisme et Electronique (CISTEME),
  Bâtiment 2 – 12, rue Gémini – 87068 Limoges

DIRECTION DE RECHERCHE UNIVERSITAIRE :

• Pascal XAVIER et Nhu-Huan NGUYEN
  Institut de Micro-électronique, Electromagnétisme et Photonique – Laboratoire d’Hyperfréquences et de Caractérisation, IMEP-LaHC, GrenobleREFERENCES
  [1] Xavier P. et al. « Dispositifs hyperfréquences à faible impact environnemental », Journée Nationale Microondes (JNM), Juin 2022, Limoges France.
  
  [2] Zakka El Nashef and al. « Low Environmental Impact RF Devices for IoT Applications », European Microwave Week (EUMW), September 2022, Milan Italy.
  
  [3] Zakka El Nashef et al. « Modélisation et Caractérisation des Antennes Biosourcés pour des Applications WIFI », Journées de Caractérisation Microondes et Matériaux (JCMM), avril 2023, Tours France.
  
  [4] Zakka El Nashef and al. « Optimized Printed Antennas Based On Paper Substrate For Wifi Applications », European Conference on Antennas and Propagation (EUCAP),March 2023, Florence Italy

• Keywords : Engineering sciences, Electronics and microelectronics - Optoelectronics, FMNT, IMEP-LaHc
• Laboratory : FMNT / IMEP-LaHc
• CEA code : IMEPLAHC-04-07-2023
• Contact : nhu-huan.nguyen@grenoble-inp.fr

IMEP-LAHC, CNRS, Chambéry, France

PhD open position in :
Arbitrary THz waveforms generator for Quantum Electronics applications

Context :
The most recent developments in 2D electron gas (2DEG) electronic circuits make it possible to consider the demonstration of quantum electronic experiments in which an electron would behave like a photon propagating in a quantum optical system [1].
However, since the coherence time of electrons is only a few tens of picoseconds (ps), it is necessary to be able to excite, control and detect
electrons with a temporal precision of the order of ps. For this purpose, we use ultrafast optoelectronics as a technique to generate ps electrical pulses exciting quantum circuits. The use of femtosecond pulsed lasers associated with very short response time photodetectors is commonly used for the generation of ps or Terahertz signals [2]. However, it has never been successfully applied to the study of quantum properties of electronic circuits.
In this research project, supported by national quantum investments (PEPR Quantique, ANR …) we develop a new technological approach by
integrating optoelectronic devices for the generation of ps electrical pulses into 2DEG circuits [3]. The precise control of the quantum state of the circuit also requires the ability to generate electronic signals of variable duration and amplitude: the design of an optoelectronic generator of arbitrary waveforms at the picosecond scale constitutes the core of this thesis proposal.

Profile sought: We are looking for a student with a background in physics, optics or electronics at
Master or Engineer level. Electromagnetism, semiconductor physics and optics are at the heart of the
proposed subject. A first research experience in one of these fields would be a plus. The candidate
should have a strong interest in experimental research, instrumentation and collaborative work.
To apply for this thesis, please send your application (single PDF file). The application should include a
cover letter with a brief description of your previous experiences, your CV, a copy of your grades and
diplomas from Bac + 3 to Bac + 5.
Thesis start date: September 2023
Contact: Pr. Jean-Francois ROUX, jean-francois.roux@univ-smb.fr
1] Bauerle et al. 2018 Rep. Prog. Phys. 81 056503 [2] Eusebe et al. 2005 JAP 98, 033711
3] Georgiou et al. ArXiV: 2001.01341

Objectives of the PhD work :
The work will focus on the development and experimental characterization of optoelectronic solutions to generate electrical pulses with adjustable duration between 1 and 10 ps and variable shape (Lorentzian, rectangle etc. …).
This research will take advantage of the experience acquired by the team in the design of THz optoelectronic components
and circuits. Two approaches will be considered: the shaping of electrical signals within the circuit or the prior shaping of the optical control pulses.

Collaboration and networking :
The research will be carried out within the PHOTO group at IMEP-LAHC, Université Savoie Mont-Blanc in Chambéry  in collaboration with the QuantECA group at the Neel Institute, CNRS in Grenoble .
Both groups benefit from equipment in high-frequency electronics, lasers, THz benches, cryogenic instrumentation, clean room
and nanofabrication lab. This project is part of the PEPR Quantique

Profile sought :
We are looking for a student with a background in physics, optics or electronics at Master or Engineer level. Electromagnetism, semiconductor physics and optics are at the heart of the proposed subject.
A first research experience in one of these fields would be a plus.
The candidate should have a strong interest in experimental research, instrumentation and collaborative work.
To apply for this thesis, please send your application (single PDF file). The application should include a cover letter with a brief description of your previous experiences, your CV, a copy of your grades and diplomas from Bac + 3 to Bac + 5.

Thesis start date :
September 2023

Contact :
Pr. Jean-Francois ROUX, jean-francois.roux@univ-smb.fr

[1] Bauerle et al. 2018 Rep. Prog. Phys. 81 056503
[2] Eusebe et al. 2005 JAP 98, 033711
[3] Georgiou et al. ArXiV: 2001.01341

• Keywords : Engineering sciences, Electronics and microelectronics - Optoelectronics, FMNT, IMEP-LaHc
• Laboratory : FMNT / IMEP-LaHc
• CEA code : IMEPLAHC-PHOTO-03-27-2023
• Contact : jean-francois.roux@univ-smb.fr