Key Skills

Job Description

Work Activities The optical properties of halide perovskite thin films are set by the positions of their atoms, including defects. Local variations in crystal phase, grain orientation, and defect density govern the photoluminescence (PL) yield and spectrum and, ultimately, solar-cell efficiency and stability. Quantifying these atomic-scale variations currently requires transmission electron microscopy (TEM), which is slow and low-throughput compared with optical measurements. In this project we ask whether the atomic structure of a perovskite film, including its defects, can be inferred from its PL and absorption alone. If so, a fast, non-destructive optical measurement becomes a quantitative crystallographic probe. To find out, we combine two major AMOLF facilities: HELIOS, an AI-guided robotic platform for perovskite film deposition and characterization, and SHINE, a unique in situ TEM with laser excitation. The resulting optical and electron-diffraction data, acquired on exactly the same regions of the same films, are used to train a neural network that infers structure from light. As a postdoc on this project you will work on: High-throughput PL screening: together with the HELIOS team, screen the photoluminescence of perovskite films prepared under varied conditions, to identify atomic structures with interesting properties that are stable in time. Correlative structural and optical mapping: combine 4D-STEM (spatially resolved electron diffraction) with PL and absorption measured on the same regions of films on TEM grids. In situ TEM under laser excitation: reproduce transient or metastable states that do not survive ex situ transfer inside the SHINE TEM. You will work in the Hybrid Nanosystems group of Wiebke Albrecht at AMOLF, in close collaboration with the Nanoscale Solar Cells group of Erik Garnett. You will be part of the HELIOS team and join its weekly work discussions. Qualifications We invite applications from highly motivated candidates with a PhD in physics, materials science, nanoscience, or a related field, and a strong background in transmission electron microscopy, including STEM-based techniques such as 4D-STEM. Experience with TEM on halide perovskites or other beam-sensitive materials is a strong plus. Experience with optical spectroscopy, data analysis in Python, or machine learning is an advantage. We especially encourage individuals from underrepresented groups to apply. Work environment The Hybrid Nanosystems group, led by Wiebke Albrecht, uses light as a tool to probe, program, and reshape nanomaterials. By combining advanced electron microscopy, single-particle optical spectroscopy, and electromagnetic simulations, we uncover how the atomic-scale structure of nanoparticles governs their response to light, and how light can drive these structures to transform. The group runs AMOLF’s light-coupled in situ TEM facility. In this project you will collaborate closely with the Nanoscale Solar Cells group of Erik Garnett, which leads AMOLF’s robotic perovskite platform. Both groups are part of AMOLF’s LMPV–Sustainable Energy Materials department, where about 50 scientists work on semiconductors for solar energy conversion and photocatalysis, with weekly departmental colloquia. AMOLF is a national institute that is part of NWO-I and initiate and performs leading fundamental research on the physics of complex forms of matter, and to create new functional materials, in partnership with academia and industry. The institute is located at Amsterdam Science Park and currently employs about 140 researchers and 80 support employees. www.amolf.nl Working conditions The working atmosphere at the institute is largely determined by young, enthusiastic, mostly foreign employees. Communication is informal and runs through short lines of communication. The position is intended as full-time (40 hours / week, 12 months / year) appointment in the service of the Netherlands Foundation of Scientific Research Institutes (NWO-I) for the duration of 2 years, with the possibility of extension by one year. Salary is in scale 10 (CAO-OI (http://www.nwo-i.nl/en/employees/employment-regulations)) which starts at 4.552 Euro’s gross per month, and a range of employment benefits (https://www.nwo-i.nl/en/working-at-nwo-i/informationforapplicants/). AMOLF assists any new foreign Postdoc with housing and visa applications and compensates their transport costs and furnishing expenses. More information? For further information about the position, please contact Wiebke Albrecht: [email protected]. Application You can respond to this vacancy online via the button below. Online screening may be part of the selection. Diversity code AMOLF is highly committed to an inclusive and diverse work environment: we want to develop talent and creativity by bringing together people from different backgrounds and cultures. We recruit and select on the basis of competencies and talents. We strongly encourage anyone with the right qualifications to apply for the vacancy, regardless of age, gender, origin, sexual orientation or physical ability. AMOLF has won the NNV Diversity Award 2022, which is awarded every two years by the Netherlands Physical Society for demonstrating the most successful implementation of equality, diversity and inclusion (EDI). Commercial activities in response to this ad are not appreciated.

Core Responsibilities

Screen perovskite films using photoluminescence and correlate optical measurements with 4D-STEM electron-diffraction maps from the same film regions. Use in situ laser-excitation TEM to study transient or metastable structures and contribute data for training neural networks to infer material structure from optical measurements.

Requirements

Applicants must have a PhD in physics, materials science, nanoscience, or a related field, and a strong background in transmission electron microscopy, including STEM-based techniques such as 4D-STEM. Experience with beam-sensitive materials and perovskites is a strong advantage; optical spectroscopy, Python data analysis, and machine learning are also advantageous.

Benefits

• Housing Assistance
• Visa Application Assistance
• Transport Cost Compensation
• Furnishing Expense Compensation
• Employment Benefits