Post-doc: Molecular Beam Epitaxy of InAs 2DEGs coupled to superconductors for superconducting quantum technologies (M/F)

Job Description

Missions

The development of superconducting quantum bits (qubits) is a major challenge in overcoming the current limitations of quantum computing. High-mobility two-dimensional electron gases (2DEGs), such as those formed in InAs-based heterostructures, are promising platforms for large-scale, gate-tunable transmons and for research on topological qubits. However, it is essential to achieve high-quality 2DEGs with minimal disorder and optimized band alignments to enhance qubit coherence and gate fidelity.

The goal of this project is to design and fabricate InAs-based 2DEGs using molecular beam epitaxy (MBE). MBE allows precise control over layer thickness, doping, and interface quality, which are crucial for minimizing scattering and maximizing electron mobility. We will focus on optimizing growth parameters, interface engineering, and band structure alignment to improve 2DEG performance. Additionally, superconducting layers will be deposited either in situ in a specially designed cluster to enable pristine interfaces or ex situ using a new sputtering system dedicated to superconductors. This will provide great flexibility in material selection and integration strategies.

Structural and chemical analyses will be conducted to identify the interface properties and their impact on transmon specifications. This work will be carried out in collaboration with researchers from the Institut Néel and CEA-PHELIQS, who specialize in X-ray diffraction and transmission electron microscopy, to ensure comprehensive material characterization.

Finally, Josephson field-effect transistors will be fabricated in a cleanroom and measured at low temperatures to evaluate the performance of these Josephson junctions. The fabrication and evaluation of the transmons will be carried out as part of the QUANTIN project in collaboration with partners from CEA-Pheliqs and LPS in Orsay.

Activity

The postdoctoral researcher will be responsible for:
- MBE growth of InAs 2DEGs and superconducting thin films.
- Characterizing the low-temperature 2DEGs InAs (e.g., mobility, carrier density) and the superconducting layers properties (critical temperature, critical current).
- Making contact and providing samples to researchers in charge of X-ray diffraction and transmission electron microscopy.
- Contributing to scientific publications and disseminating results at conferences and workshops.

Your Profil

Skills

- The candidate must hold a Ph.D. in physics, materials science, nanotechnology, or a related field.
Expertise in the following areas will be particularly valued:
- Experience in molecular beam epitaxy (MBE)
- Skills in nanomaterial and surface characterization.
- Knowledge of low temperature electron transport measurement.
- Ability to work in a team and interact with researchers from various disciplines.
- Excellent communication and scientific writing skills in English.

Your Work Environment

This job proposal is funded by ANR PEPR Technologies Quantique through the project QUANTIN, which provides access to state-of-the-art MBE and characterization facilities, as well as a collaborative network of experts in quantum technologies.

The research will be carried out at the Institut Néel, benefiting from a large pool of local research and with existing international collaborations.
The postdoc researcher will be integrated in the "Nanophysics and Semiconductors" team of the "Physics - Light - Material" (PLUM) department.

The Institut NÉEL is a CNRS unit (UPR 2940) under agreement with the University Grenoble Alpes. The laboratory is related to the CNRS Physique. It is located in Grenoble, in the heart of a unique scientific, industrial and cultural environment. It 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 consists of 450 employees, including 175 researchers.
CNRS is a public, scientific and technological organisation.
The core mandate is to identify, carry out ou have carried out, either alone or with partners, all research that advances science or contributes to the country's economic, social, and cultural progress. Internationally recognised for the excellence of its scientific research, the CNRS is a reference in the world of research and development, as well as for the general public.

Compensation and benefits

Compensation

Between 3041 € and 3467 € gross salary according to experience

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

The research professions