PhD- student: Harnessing phase transitions for optical information processing

Work Activities
This PhD project will investigate how phase transitions can be harnessed for information processing with light. Near a continuous phase transition, the susceptibility of a material can increase strongly. This allows weak input signals to generate large responses, which can in turn reduce the optical energy required for an operation. However, critical slowing down and enhanced fluctuations may limit processing speed and accuracy. The main objective of this PhD project is to quantify this trade-off between energy consumption, speed and accuracy in information processing near a phase transition, and to determine how it depends on properties of the signal such as amplitude and bandwidth.

The project builds on a recent work by the host group [Keijsers et al., Nature Photon. 19, 733 (2025)], where signatures of a phase transition were observed in the nonlinear response of a laser-driven optical cavity containing a perovskite crystal. The first objective is to characterize the spectral and temporal response of this system near the transition, which is expected to include memory effects and strong fluctuations. Next, controlled time-dependent signals and benchmark optical information-processing operations will be used to compare performance at different distances from the phase transition. Experiments will be combined with theoretical modelling, statistical data analysis, and numerical simulations to identify the governing mechanisms and to determine whether and how proximity to a phase transition offers an advantage for processing certain signals. The project is primarily experimental and will involve optical cavity measurements, materials characterization and, where needed, nanofabrication. Its expected outcome is an experimentally tested framework for designing photonic information-processing systems that exploit phase-transition physics.

Qualifications
You have an MSc degree in physics, optics, photonics, nanoscience, or a related field. Laboratory experience in optics or photonics is preferable but not strictly necessary. A background in, or strong interest in, one or more of the following areas is valued: nonlinear dynamics, condensed-matter physics, and stochastic processes. The ideal candidate is an experimentalist who enjoys not only setting up and performing complex experiments, but also thinking deeply about the results and modelling them. Applicants are not expected to bring expertise in all listed areas; the required methods will be learned during the project.

This is a collaborative project between AMOLF and Utrecht University. Your host will be the Interacting Photons group led by Prof. Said R. K. Rodriguez at AMOLF, but you will also work part time at Utrecht University with Prof. Allard Mosk and his group. We are therefore looking for someone who has the personal and communication skills required to connect two groups at different locations (half hour away), besides being able to work independently. The appointment also includes a contribution to teaching at Utrecht University and participation in the relevant training programs.

Work environment
AMOLF is a 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

In the Interacting Photons group, we search for new physics emerging from photon interactions. As a testbed for new ideas, we use nonlinear nanophotonic resonators. We are driven by fundamental physics questions relevant to improve the energy efficiency, speed, and precision of optical technologies such as novel sensors and computers.

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 four years
• The starting salary is 3.115 Euro’s gross per month and a range of employment benefits.
• After successful completion of the PhD research a PhD degree will be granted at a Dutch University.
• Several courses are offered, specially developed for PhD-students.
• AMOLF assists any new foreign PhD-student with housing and visa applications and compensates their transport costs and furnishing expenses.

More information?
For further information about the position, please contact Said R.K. Rodriguez: s.rodriguez@amolf.nl

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).

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PhD: Physics-Informed Machine Learning for Semiconductor Metrology

Work Activities
How can we combine machine learning and physics to recover nanoscale information from imperfect images?
Modern computer chips are built with features only a few nanometers across, yet manufacturers need to measure these structures with extraordinary precision and do so quickly enough to keep up with large-scale production. This creates a fascinating computational challenge: how can we infer hidden physical properties from limited, noisy, and low-resolution measurement data?

In this project, you will develop a novel physics-informed machine learning approach that integrates physical simulations of the measurement process with its inverse reconstruction. A key challenge is the data-driven design of the experimental setup: exploring how the choice of measurements and configurations can be optimized to extract the most useful information for reliable parameter reconstruction.

You will work in close collaboration with the research department at ASML, the Centrum Wiskunde & Informatica (CWI, Prof. dr. Tristan van Leeuwen), and the AI4Science Lab, Informatics Institute, University of Amsterdam (dr. Patrick Forré), combining industrial relevance with academic depth in computational science and mathematical modeling.

Qualifications
You have (or soon will have) a MSc degree in computer science, machine learning, artificial intelligence, applied mathematics, physics, or a related discipline, meeting the Dutch university requirements for entry into a PhD program. A background in machine learning, inverse problems, scientific computing, or related data-driven methods is highly desirable. You are curious about combining physical modeling with data-driven methods and are motivated to work at the interface of academia and industry. Strong analytical skills, a collaborative mindset, and proficiency in verbal and written English are essential.

Work environment
ARCNL performs fundamental research, focusing on the physics and chemistry involved in current and future key technologies in nanolithography, primarily for the semiconductor industry. While the academic setting and research style are geared towards establishing scientific excellence, the topics in ARCNL’s research program are intimately connected with the interests of the industrial partner ASML. The institute is located at Amsterdam Science Park and currently employs about 100 persons of which 65 are ambitious (young) researchers from all over the globe. www.arcnl.nl

Working conditions
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 four years, with a starting salary of gross € 3.115 per month and a range of employment benefits. After successful completion of the PhD research a PhD degree will be granted at a Dutch University. Several courses are offered, specially developed for PhD-students. ARCNL assists any new foreign PhD-student with housing and visa applications and compensates their transport costs and furnishing expenses.

More information?
For further information about the position, please contact Lyuba Amitonova: l.amitonova@arcnl.nl and Maximilian Lipp (m.lipp@arcnl.nl).

Application
You can respond to this vacancy online via the button below.

Online screening may be part of the selection.

Diversity code
ARCNL 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.

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Postdoc : Generating extreme ultraviolet light from plasma with a 2µm laser

Work Activities
This experiment-oriented postdoctoral position lies at the interface between fundamental physics and industrial application. It is part of activities in ARCNL’s Source Department. The research activities of the Source Department and its EUV Plasma Processes group aim at the atomic- and molecular-level understanding of the fundamental dynamics in the operation of contemporary and future plasma-based sources of extreme-ultraviolet (EUV) light for nanolithography.

In our group’s research we, for example, uncovered the quantum origins of the generated EUV light [Torretti, Nature Comms. Nature Commun. 11, (2020)], found a universal law for expanding plasma [Sheil, Phys. Rev. Lett. 133, (2024)], and found that less than half the initial droplet volume is present on thin tin sheet targets as used in EUV sources [Liu, Phys. Rev. Appl. 20, (2023)], and work on an alternative EUV source solution [Mostafa, Appl. Phys. Lett. 123, (2023)] – a concept that is most relevant for the current vacancy.

Background
The revolutionary introduction of EUV lithography was the culmination of several decades of collaborative work between industry and science – a Project Apollo of the digital age. The short, 13.5-nm EUV wavelength enables patterning the smallest, smartest, and most energy-efficient features on chips. The required 13.5-nm radiation is generated from plasma that is produced from tiny tin droplets that are heated by powerful laser pulses. At ARCNL, we are now thinking about the next generation of light sources: Can we make more energy efficient and more powerful EUV light sources?

Project goal
To identify what light source will power the next generation of lithography machines, we need to understand what plasma conditions are optimal for producing light from plasma, but also we need to understand how such plasma should be generated, and what laser technology should be used. You will join an interdisciplinary team of several PhD students and postdocs in ARCNL’s highly cohesive Source Department and have as an objective to design & execute experiments, and work with advanced laser technologies, to understand the emission of light and ions from plasma that you generate.

Qualifications

• You have (or will soon obtain) a PhD in (Applied) Physics.
• Knowledge of experimental laser and/or plasma physics is an asset, especially if combined with strong hands-on laboratory skills.
• Programming experience, particularly in Python, is welcomed.
• Strong verbal and written communication skills in English are required.

Work environment
The Advanced Research Center for Nanolithography (ARCNL) focuses on the fundamental physics and chemistry involved in current and future key technologies in nanolithography, primarily for the semiconductor industry. ARCNL is a public-private partnership between the Dutch Research Council (NWO), the University of Amsterdam (UvA), the VU University Amsterdam (VU), the University of Groningen (UG), and the semiconductor equipment manufacturer ASML. ARCNL is located at the Amsterdam Science Park, The Netherlands, and has a size of approximately 100 scientists and support staff. See also www.arcnl.nl

Working conditions
The position is intended as full-time (40 hrs / week, 12 months / year) appointment in the service of the Netherlands Foundation for Scientific Research Institutes (NWO-I) for the duration of up to 3 years, with a starting salary of €4,552 gross per month, scale 10 (CAO-OI), and a range of employment benefits. A favorable tax agreement, the ‘30% ruling’, may apply to non-Dutch applicants. ARCNL assists any new foreign researchers with housing, subject to availability, and visa applications and compensates their transport costs and furnishing expenses.

More information?
For further information about the position, please contact:

Dr. Oscar Versolato
Group leader EUV Plasma Processes
E-mail: versolato@arcnl.nl
Phone: +31 (0)20-851 7100

Application
You can respond to this vacancy online via the button below.

Please send your:

• Resume
• Motivation letter on why you want to join the group (max. 1 page).

Online screening may be part of the selection.

Diversity code
ARCNL 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.

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Postdoc “NanoXUV” – Nonlinear metaphotonics for UV semiconductor metrology

Work Activities
In the “NanoXUV” research program the Resonant Nanophotonics team at AMOLF (lead: Femius Koenderink) and the High-Harmonic Generation and EUV Science team at ARCNL (lead: Peter Kraus) develop nanophotonic structures that convert infrared wavelengths to light of very short wavelength, in the UV and even extreme ultraviolet. The need for such a technology comes from the the extreme miniaturisation of micro-electronics, which places extreme demands not just on nanofabrication, but also on inspection methods that visualize the manufactured devices. While optical inspection methods have the advantage of being fast and non-destructive, they typically face the challenge that features that are to be resolved are much smaller than the diffraction limit associated with the usual visible or infrared wavelengths. In this program we envision optical metasurfaces pumped by femtosecond infrared pulses that emit XUV light for metrology.

How do you design optical metasurfaces that efficiently radiate UV light by nonlinear frequency conversion through 3rd, 5th and high-harmonic generation? How do the geometry of meta-atoms and their arrangement in the metasurface translate into bright sources, and how do you generate that emit beams that are structured in amplitude, phase and polarization for super-resolution metrology? We offer a 2-year postdoctoral fellowship to tackling these questions, working in both groups and with PhD students engaged in metasurfaces, metrology, and solid-state HHG. The research targets both academic and applied breakthroughs, for which we will frequently interact with industry partners at ASML. Our team has everything required for this project available in house, including electromagnetic design and theory, the cleanroom nanofabrication facilities to realize optical metasurfaces, and ultrafast laser setups for THG and HHG generation and microscopy.

Qualifications
Mandatory:
You have (or will receive in the near future) a PhD degree in nanophotonics and /or ultrafast light-matter interaction. You enjoy performing experiments and analysis to stepwise build a deeper understanding of complex physical mechanisms. For this position, we are particularly looking for a candidate who is eager to span disciplines, combining state-of-the-art ultrafast laser optics with design, fabrication, and spectroscopy of metasurfaces. A solid background in both optics/optics engineering and condensed matter physics would be ideal.

Experience in one or more of the following topics is expected

• Nanophotonics of e.g. metasurfaces, photonic crystals, or plasmonic structures
• Ultrafast lasers and optics and /or advanced microscopy of nanophotonic systems
• Condensed matter physics & fundamental optical processes in solids

Additionally proficiency with data analysis (Python, MATLAB), an interest in electromagnetic simulation and nanofabrication, as well as very good verbal and written communication skills in English are expected.

Work environment
About the institutes:

AMOLF is a national research institute and is part of NWO-I. Its mission is to initiate and perform 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 150 researchers and 80 support employees. www.amolf.nl.

ARCNL performs fundamental research, focusing on the physics and chemistry involved in current and future key technologies in nanolithography, primarily for the semiconductor industry. While the academic setting and research style are geared towards establishing scientific excellence, the topics in ARCNL’s research program are intimately connected with the interests of the industrial partner ASML. The institute is located right next to AMOLF and currently employs about 65 researchers and 35 support employees. www.arcnl.nl

About the groups:

Resonant Nanophotonics at AMOLF The research activities in the Resonant Nanophotonics group at AMOLF aim at developing nanoscale photonic structures, such as plasmonic and dielectric metasurfaces, to control scattering, emission, amplification and detection of light. The group spans the entire research cycle from developing advanced nanophotonics concepts using state of the art theory and numerical design, to nanofabrication of designed structures in the Amsterdam NanoLab cleanroom at AMOLF and the development of state of the art optical scatterometry and microscopy methods.

High Harmonic Generation and EUV Science at ARCNL The HHG & EUV Science Group investigates the high-harmonic generation (HHG) phenomenon in various media, including gases, solids such as semiconductors, and strongly correlated materials, as well as nanostructures like metasurfaces. Our objective is to understand and enhance the efficiency of the HHG process to broaden its potential applications. This involves developing new experimental configurations and novel sources in the XUV/soft-X-ray domain. Moreover, we are exploring the possible applications of XUV radiation in imaging and metrology with a nanometer resolution, specifically in holography and scatterometry. We also utilize high-harmonics in ultrafast transient XUV spectroscopy to probe the dynamics of electronic and atomic systems with femtosecond time resolution. Our recent HHG experiments conducted on solids showcase the potential for manipulating optical emission (deactivation) solely through light, which can have practical applications in high-resolution imaging and super-resolution microscopy at the nanoscale.

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
• Salary is in scale 10 (CAO-OI) which starts at 4.552 Euro’s gross per month, and a range of employment benefits.
• 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 Femius Koenderink: f.koenderink@amolf.nl

Application
You can respond to this vacancy online via the button below.

Online screening may be part of the selection.

Diversity code
AMOLF and ARCNL are 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.

Commercial activities in response to this ad are not appreciated.

PhD: AI-assisted discovery of chiral perovskites in nanophotonic environments

Work Activities
AI-assisted discovery of chiral perovskite (quantum) emitters. You will leverage an AI-assisted materials optimization robot being developed at AMOLF as a route to rapid, closed-loop synthesis and characterization across large perovskite parameter spaces. You will optimize directly for figures of merit such as chirality, emission wavelength, brightness, and stability. Because optical excitation of perovskites can move atoms around, sculpting the optical field in time and space can enable programmable optical functions. By conducting approximately 1 million optical experiments in parallel using a spatial light modulator and hyperspectral camera, you will explore chemical and processing landscapes in days that would otherwise take a student a lifetime to cover systematically. Special attention will be paid to 2D and related low-dimensional perovskites, with the aim to understand if intrinsically strong material chirality is a necessary condition for reaching strong programmable chirality.

Materials discovery in non-trivial optical environments. Building on the first thrust, you will introduce a new paradigm in optoelectronic device design: to synthesize and screen perovskite emitters directly on substrates that already provide a structured optical response. In a material that can be sculpted by the optical field, this provides the opportunity for a self-optimizing response – the local optical field imprints a symmetry on the material, which then amplifies the light-matter coupling. In the conventional workflow, one first finds a material with good intrinsic properties and only then designs the surrounding cavity, resonance, or metasurface. You will reverse that order, replacing an optically inert glass slide by a substrate with a designed resonance arising from refractive-index structuring (optical metasurface). Thin perovskite films spun onto such a substrate will respond most strongly when their emission (absorption) spectrum aligns with the photonic resonance. Likewise, if the figure of merit is chirality and the substrate itself has chiral optical response, one can search for materials whose intrinsic emission (absorption) couples most effectively to that environment. In this way, the optical structure of the substrate transforms the material on top into exactly what it needs for maximal performance. Such exploration offers tantalizing opportunities to study the impact of local versus nonlocal optical resonances in the context of material optimization. How does the spatial extent of the photonic resonance affect the material symmetry? Does the optical field profile induce spatially varying chiral properties in the perovskite? Understanding the coupling between photonic environment and material crystallization poses completely new opportunities in material synthesis for advanced photonic integration and technologies.

Qualifications
You have a Msc degree in physics, chemistry, materials science, engineering or another scientific discipline. You have an analytical mind with the ability to think about a problem and come up with logical and creative solutions. You can work independently and also enjoy collaborating in a team. You enjoy actively engaging others to learn new concepts and experimental methods. You are eager to give and receive feedback and see it as an opportunity for personal and professional growth. You have excellent communication skills in English. You are responsible, reliable and dedicated while caring about the well-being of yourself and your colleagues. You value and cherish diversity of background, opinion and ability and see a team as more than the sum of its parts.

Work environment
This is a collaborative project between AMOLF and the University of Amsterdam. Your contract and host group will be the Nanoscale Solar Cells group led by Erik Garnett at AMOLF amolf.nl/research-groups/nanoscale-solar-cells but you will also work part time at the Van der Waals-Zeeman institute of the University of Amsterdam iop.uva.nl/wzi/wzi.html with professors Sander Mann mannlab.nl and Jorik van de Groep vandegroeplab.com in the department of physics. These institutes are located next to each other in the Amsterdam Science Park. This collaborative position opens up many experimental and theoretical tools and facilities needed for the project including the AI-assisted automated synthesis and characterization robot, the AMOLF nanolab www.amolf.nl/nanolab, ultrafast, chiral and single photon microscopes and full-wave numerical simulations and analytical models. We share a vibrant, inclusive and collaborative work culture that welcomes scientists and engineers with diverse backgrounds and skills. There is a very active staff association organizing regular social activities throughout the year to enrich the work experience and community. There is excellent support staff to help with the more technical and administrative parts of the project.

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 four years
• The starting salary is 3.115 Euro’s gross per month and a range of employment benefits.
• After successful completion of the PhD research a PhD degree will be granted at a Dutch University.
• Several courses are offered, specially developed for PhD-students.
• AMOLF assists any new foreign PhD-student with housing and visa applications and compensates their transport costs and furnishing expenses.

More information?
For further information about the position or specific questions, please contact Erik Garnett: e.garnett@amolf.nl

Application
You can respond to this vacancy online via the button below. Please apply by submitting a CV and cover letter explaining why you want this specific PhD position, what you can contribute and what you would like to learn. We will start evaluating applications on June 15th and will continue until the position is filled.

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.