GeePs Postdoc

##### **20/01/2026**

**Function :** Post-doctorate

**Contract :** Full time Scientific fixed term

**Starting date:** 01.06.2026

**Duration:** 12 months

**Workplace:** CentraleSupélec, Group of electrical engineering of Paris (GeePs), UMR 8507.

**Education:** Level 8 – (Doctorate)

**Reference :** PD-IOTA-441-2026

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## **GeePs**

The GeePs is a CNRS joint research centre situated on the plateau de Saclay in the campus of CentraleSupélec and the École Polytechnique, within a few minutes travel distance of each other. The successful candidate will be hired under a CentraleSupélec contract, and will work at the GeePs laboratory, where they will have access to the infrastructure necessary for simulation.

## **Main missions**

The mission concerns development of high efficiency solar cells based on a novel design, the three terminal selective band offset tandem solar cell (3T-SBOB) recently patented by the GeePs laboratory. The mission will be carried out in context is the IOTA project (InnOvative Tandem Architectures), which is part of the French nations strategic programme PEPR\_TASE for energy systems and renewable energy. The 3T-SBOB tandem solar cell consists of a high gap « top » solar cell fabricated on a silicon interdigitated back contact (IBC) low bandgap « bottom » solar cell. The mission contributes to the development of three types of top cell and their integration on the IBC.

In this context, we require a postdoctoral researcher for a period of twelve months to develop theoretical models of the 3T-SOB for the three materials systems being considered for the top cell. The three top cells to be simulated are perovskite, organic, and CIGS solar cells. The the position will require close interaction with partners responsible for fabricating these three types of 3T-SBOB, and with characterisation teams. It will provide analysis on device performance and identify routes for optimisation with regards to light management, electronic transport properties and cell composition and geometry. This work will be carried out in the context of the tandem cell integration work packackage WP4, and benefit from interactions with the coupled integration task 4.1 led by collaborators at INL in Lyon.

## **Activities**

The successful postdoctoral candidate will work closely with James Connolly at GeePs and will collaborate with Mohammed Amara at INL responsible for coupled simulation of complete tandem solar cells task 4.1. The work will benefit from shared simulation servers and commercial numerical modelling software which requires mastery of its scripting language. They will be provided with working models of 3T-SBOB devices which will serve as basis for the first task which will be verification of organic and perovskite materials parameters and models. A second task will involve the development on the same basis of a 3T-SBOB model with a CIGS top cell, using existing CIGS solar cell models, and in collaboration with experts on this materials famils in the IOTA project.

The work will be carried out at the Group of Electrical Engineering of Paris (GeePs). Travel will be required mainly in the context of project meetings or conferences where the candidate will present activities carried out in the project and results obtained.

## **Profile**

### **Skills**

The candidate must hold a doctorate in physics, preferably in the field of photovoltaics, with knowledge of semiconductor and device physics, and an experience in numerical modelling with finite element methods of solar cell devices. Knowledge of some or all of the materials involved is an advantage.

### **Experience**

– Interdigitated back contact Si solar cells

– Multijunction photovoltaic devices

– Finite element numerical modelling of solar cells

– Properties of thin film materials for photovoltaics

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## **Contact**

Send a CV et letter of motivation to james.connolly@centralesupelec.fr before Feb. 28th 2026.