PhD Position : Structural studies of superconductor–semiconductor interfaces

COFUND QuanG; France; Sur place; EUR 21 000 - 27 000; Plein temps

Résumé du poste

COFUND QuanG Research invites applications for a PhD position at the Institut Néel. The project focuses on InAs/Sn nanostructures and tunable Josephson junctions for quantum devices. A Master’s degree is required and MSCA mobility rules apply.

The three-year funded PhD will use TEM, GPA, EDX and advanced imaging to understand interfaces, with collaboration across the UK and France. Starting Feb 1, 2027.

Qualifications

• Master’s degree or an equivalent qualification by the deadline.
• MSCA mobility rule applies: must not have resided in France for more than 12 months in the last 36 months.

Responsabilités

• Characterize atomic and chemical structure of interfaces in InAs/Sn nanostructures.
• Analyze impact of surface preparation and growth conditions on Josephson junction performance.
• Perform TEM, GPA, EDX analyses and growth modeling as part of the project.
• Collaborate with international partners for measurements and data interpretation.

Connaissances

Semiconductor and solid-state physics

Formation

Master’s degree

Description du poste

Organisation/Company COFUND QuanG Research Field Physics Researcher Profile First Stage Researcher (R1) Positions PhD Positions Application Deadline 7 Sep 2026 - 12:00 (Europe/Paris) Country France Type of Contract Temporary Job Status Full-time Offer Starting Date 1 Feb 2027 Is the job funded through the EU Research Framework Programme? Horizon Europe – COFUND Reference Number 101261699 Is the Job related to staff position within a Research Infrastructure? No

Offer Description

General Scope:
This thesis project, conducted at the Institut Néel, aims to study InAs/Sn nanostructures—developed for tunable Josephson junctions in quantum devices—using high-resolution transmission electron microscopy (TEM). Currently, quantum processors suffer from short coherence times due to the quality of the interfaces and materials, particularly the presence of an amorphous oxide in the junction. To
address this challenge, InAs nanostructures coated with Sn are being developed to fabricate tunable Josephson junctions incorporated into transmon qubit, using the InAs semiconductor as the weak link. InAs two-dimensional electron gases coated with tin are fabricated by molecular beam epitaxy. The mechanisms governing the growth of Sn on InAs and other III-V semiconductors remain poorly understood. Imaging Sn/InAs interfaces at atomic resolution using a transmission electron microscope (TEM) gives crucial information on material quality, structure, and chemistry, in particular when coupled with X-ray diffraction studies and low-temperature transport properties. Importantly, in situ TEM measurement of electronic transport through metal/semiconductor junctions is a revolutionary approach that will be used to correlate atomic-scale interface properties with macroscopic transport properties.

PhD Subject:
The objective of this thesis is to characterize the atomic and chemical structure of the aforementioned interfaces and analyze the impact of surface preparation and growth conditions to improve the performance of Josephson junctions. The methodology combines TEM, geometric phase analysis (GPA), chemical analysis (EDX), and growth modeling. Experiments using 4D-STEM coupled with electron ptychography will provide further insight into the distribution of chemical elements and 3D strain around the interfaces in these structures. The expected results include a better understanding of the growth mechanisms of Sn on III-V’s, the identification of optimal conditions for minimizing defects, and the optimization of strain distribution, paving the way for more stable and high-performance quantum devices. Structural properties will be investigated using state-of-the-art high-resolution TEM at the Institut Néel to guide the optimization of growth conditions and the development of growth models. As a powerful and complementary technique, X-ray diffraction experiments performed at PHELIQS will provide complementary information on the structural properties. Finally, in collaboration with international partners in the UK, electrical transport measurements will be performed to determine carrier properties in the structures.

Required Skills:

• Required Skills:Semiconductor and solid-state physics

Applicants must hold a Master’s degree or an equivalent qualification by the application deadline and must not already hold a doctoral degree. Applicants must also comply with the MSCA mobility rule: they must not have resided or carried out their main activity (work, studies, etc.) in France for more than 12 months during the 36 months immediately preceding the application deadline. Applicants must not be current employees of the host laboratory. There are no nationality or age restrictions.

Additional comments

About the QuanG2 PhD Call

This PhD position is offered as part of the QuanG2 PhD Call for Applications, a doctoral programme coordinated by Université Grenoble Alpes and dedicated to training the next generation of researchers in quantum science and technology. The programme offers fully funded three-year PhD positions within the Grenoble quantum research ecosystem, providing doctoral candidates with a high-level international research environment and dedicated funding for their research and training activities.