Postdoc: Probing electron-photon correlations using CL spectroscopy

Work Activities
Cathodoluminescence (CL), the light emitted when a fast electron interacts with a material, is a powerful probe of optical and electronic properties at the nanoscale. Each emission event is a quantum-mechanical electron-photon interaction, and the correlations between the electron and the emitted photons carry information that conventional CL does not use. This project is part of the NXTGEN Hightech programme of the Dutch National Growth Fund, with TU Delft, DELMIC, Amsterdam Scientific Instruments, and Technolution. We push CL in two directions: towards high throughput in a multi-beam electron microscope for compound semiconductor metrology (GaN, SiC, GaAs), and towards fundamental studies of electron-photon correlations and entanglement.

As a postdoc at AMOLF you will work on:

• High-throughput CL with a single beam: identify what limits the imaging speed of a CL system (scanning, detector response, signal level, data volume) and optimize it using fast detectors such as multi-pixel photon and electron counters (TimePic), smart scanning strategies and data reduction.
• Multi-beam CL: design and test how to collect and detect CL from many electron beamlets at once, from "ensemble CL" to flag and localize defects towards imaging of individual beamlets. You will build an optical testbench that emulates an array of electron beams and develop a prototype with DELMIC that is tested in the multi-beam microscope at TU Delft.
• Correlative measurements: you will combine CL with single-electron counting, detecting each emitted photon in coincidence with the electron that excited it, to access photon statistics, emission dynamics and electron-photon correlations.
• Electron-photon entanglement: you will investigate whether the electron and photon emitted in the same event are entangled, using the laterally coherent fraction of the electron beam to excite emitters coherently. By erasing the which-path information in the scattering geometry (a quantum eraser) you will test whether interference of the emission is observed, giving insight into the coherence of electron-light-matter scattering.

You will work in the Photonic Materials group of Prof. Albert Polman at AMOLF, in close collaboration with the TU Delft team, DELMIC, Amsterdam Scientific Instruments, and Technolution, with regular joint meetings and workshops.

Qualifications
We invite applications from highly motivated candidates with a PhD in physics, optics, materials science or engineering, and a keen interest in cathodoluminescence, electron microscopy, quantum optics and instrument development. Experience with optical instrumentation, fast detectors, photon-correlation or coincidence measurements, optical simulation, or data acquisition and analysis is an advantage. We especially encourage individuals from underrepresented groups to apply.

Work environment
The Photonic Materials group (www.erbium.nl), led by Prof. Albert Polman, studies light-matter interactions at the nanoscale. The group pioneered cathodoluminescence spectroscopy as a nanophotonics probe, and its CL setup was the prototype for the SPARC system commercialized by DELMIC. The group is an international team of PhD students, postdocs and master students that work in a collaborative atmosphere with many social group activities. Every week we hold a group meeting and departmental colloquium and poster sessions. We also regularly organize an international group labtour.

In this project you will collaborate closely with TU Delft, DELMIC and Technolution, with biweekly virtual meetings, quarterly workshops and an annual event with external partners from industry. We offer a highly collaborative and supportive environment, fostering strong connections both within the group and with our national and international partners.

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

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 three 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 Albert Polman: a.polman@amolf.nl

Application
You can respond to this vacancy online via the button below. Applications are being reviewed until the vacancy 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.

PhD position: Optical metasurfaces controlling quantum electron wavepackets

Work Activities
In this project, you will study the fundamental interactions between high-energy electrons and extreme light fields in a scanning electron microscope (SEM). Gaining control over these interactions may lead to new forms of electron microscopy that exploit the quantum-mechanical nature of electron wavepackets. The project uses an emerging technique, photon-induced near-field electron microscopy (PINEM), in which electrons in a 1-ps-pulsed electron beam exchange energy with a strongly confined optical near field generated by intense laser pulses. This interaction changes the electrons' energy, which in turn modifies the electron wavepacket in space and time, creating, for example, attosecond electron pulse trains. You will develop specially designed non-local optical metasurfaces to control the interaction of the electrons with the strong light fields. Structured 2D dielectrics integrated with nanometer-thin transition-metal dichalcogenide layers, exhibiting strong optical resonances, will be designed to enhance and control the coupling in an ultrafast 1-30 keV SEM.

Your research will include:

• PINEM and metasurface design (years 1): learn to operate the ultrafast SEM at AMOLF, study PINEM theory and modeling, and design and fabricate metasurfaces in the Amsterdam NanoCenter cleanroom.
• PINEM-metasurface integration (year 2): measure the electron-light interaction of optimized metasurfaces and tailor electron wavepackets by design, including through two subsequent coherent PINEM interactions.
• Coherence and entanglement (year 3-4): investigate correlations between electron energy loss and cathodoluminescence, and test a quantum-eraser geometry in which the which-path information is erased.

The project combines the ultrafast electron-light-matter interaction and cathodoluminescence expertise of Prof. Albert Polman (AMOLF) with metasurface design, fabrication and optical characterization expertise of Dr. Jorik van de Groep (University of Amsterdam). You will be based in the Photonic Materials group of Prof. Polman at AMOLF, with close interaction with the 2D Nanophotonics group of Dr. van de Groep at the University of Amsterdam.

Qualifications
We invite applications from highly motivated candidates with a strong background in physics and a keen interest in nanophotonics, quantum physics, nanofabrication and electron microscopy. We especially encourage individuals from underrepresented groups to apply. Prospective PhD candidates must hold an MSc degree in physics or equivalent qualification.

Work environment
Work environment The Photonic Materials group (www.erbium.nl), led by Prof. Albert Polman, studies light-matter interactions at the nanoscale. The group is composed of an international team of PhD students, postdocs and master students that work in a collaborative atmosphere with many social group activities. Every week we hold a group meeting and departmental colloquium and poster sessions. We also regularly organize an international group labtour.

AMOLF provides state-of-the-art ultrafast electron microscopy systems for time-, angle- and polarization-resolved cathodoluminescence spectroscopy and PINEM, and a shared cleanroom for nanofabrication and characterization (Amsterdam NanoCenter). We offer a highly collaborative and supportive environment, fostering strong connections both within the group and with our national and international partners. PhD students benefit from a variety of courses designed to enhance their research skills.

AMOLF is a part of NWO-I and initiates and performs leading fundamental research on the physics of complex forms of matter, and creates 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 The 2D Nanophotonics lab (https://vandegroeplab.com), led by Dr. Jorik van de Groep, studies nanophotonic metasurfaces that enable active control over light by harnessing the highly tunable optical properties of two-dimensional quantum materials. By combining resonant metallic and semiconductor nanostructures with exciton resonances in 2D semiconductors, we create dynamic metasurfaces that actively tune light emission, scattering, and absorption at the nanoscale. Our group is part of the Institute of Physics at the University of Amsterdam (https://iop.uva.nl) and works in a collaborative atmosphere with other researchers within the department and (inter)national collaborators.

Working conditions

• The working atmosphere at the institute is largely determined by young, enthusiastic, mostly non-Dutch 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 for the duration of four years. The planned start date is December 1, 2026. · The starting salary is 3.115 Euros gross per month and a range of employment benefits.
• After successful completion of the PhD research a PhD degree will be granted at the University of Amsterdam.
• 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 Albert Polman: a.polman@amolf.nl and Jorik van de Groep: j.vandegroep@uva.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).

Commercial activities in response to this ad are not appreciated.

Postdoc: Probing electron-photon correlations using CL spectroscopy

Work Activities
Cathodoluminescence (CL), the light emitted when a fast electron interacts with a material, is a powerful probe of optical and electronic properties at the nanoscale. Each emission event is a quantum-mechanical electron-photon interaction, and the correlations between the electron and the emitted photons carry information that conventional CL does not use. This project is part of the NXTGEN Hightech programme of the Dutch National Growth Fund, with TU Delft, DELMIC, Amsterdam Scientific Instruments, and Technolution. We push CL in two directions: towards high throughput in a multi-beam electron microscope for compound semiconductor metrology (GaN, SiC, GaAs), and towards fundamental studies of electron-photon correlations and entanglement.

As a postdoc at AMOLF you will work on:

• High-throughput CL with a single beam: identify what limits the imaging speed of a CL system (scanning, detector response, signal level, data volume) and optimize it using fast detectors such as multi-pixel photon and electron counters (TimePic), smart scanning strategies and data reduction.
• Multi-beam CL: design and test how to collect and detect CL from many electron beamlets at once, from "ensemble CL" to flag and localize defects towards imaging of individual beamlets. You will build an optical testbench that emulates an array of electron beams and develop a prototype with DELMIC that is tested in the multi-beam microscope at TU Delft.
• Correlative measurements: you will combine CL with single-electron counting, detecting each emitted photon in coincidence with the electron that excited it, to access photon statistics, emission dynamics and electron-photon correlations.
• Electron-photon entanglement: you will investigate whether the electron and photon emitted in the same event are entangled, using the laterally coherent fraction of the electron beam to excite emitters coherently. By erasing the which-path information in the scattering geometry (a quantum eraser) you will test whether interference of the emission is observed, giving insight into the coherence of electron-light-matter scattering.

You will work in the Photonic Materials group of Prof. Albert Polman at AMOLF, in close collaboration with the TU Delft team, DELMIC, Amsterdam Scientific Instruments, and Technolution, with regular joint meetings and workshops.

Qualifications
We invite applications from highly motivated candidates with a PhD in physics, optics, materials science or engineering, and a keen interest in cathodoluminescence, electron microscopy, quantum optics and instrument development. Experience with optical instrumentation, fast detectors, photon-correlation or coincidence measurements, optical simulation, or data acquisition and analysis is an advantage. We especially encourage individuals from underrepresented groups to apply.

Work environment
The Photonic Materials group (www.erbium.nl), led by Prof. Albert Polman, studies light-matter interactions at the nanoscale. The group pioneered cathodoluminescence spectroscopy as a nanophotonics probe, and its CL setup was the prototype for the SPARC system commercialized by DELMIC. The group is an international team of PhD students, postdocs and master students that work in a collaborative atmosphere with many social group activities. Every week we hold a group meeting and departmental colloquium and poster sessions. We also regularly organize an international group labtour.

In this project you will collaborate closely with TU Delft, DELMIC and Technolution, with biweekly virtual meetings, quarterly workshops and an annual event with external partners from industry. We offer a highly collaborative and supportive environment, fostering strong connections both within the group and with our national and international partners.

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

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 three 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 Albert Polman: a.polman@amolf.nl

Application
You can respond to this vacancy online via the button below. Applications are being reviewed until the vacancy 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.

PhD position: Optical metasurfaces controlling quantum electron wavepackets

Work Activities
In this project, you will study the fundamental interactions between high-energy electrons and extreme light fields in a scanning electron microscope (SEM). Gaining control over these interactions may lead to new forms of electron microscopy that exploit the quantum-mechanical nature of electron wavepackets. The project uses an emerging technique, photon-induced near-field electron microscopy (PINEM), in which electrons in a 1-ps-pulsed electron beam exchange energy with a strongly confined optical near field generated by intense laser pulses. This interaction changes the electrons' energy, which in turn modifies the electron wavepacket in space and time, creating, for example, attosecond electron pulse trains. You will develop specially designed non-local optical metasurfaces to control the interaction of the electrons with the strong light fields. Structured 2D dielectrics integrated with nanometer-thin transition-metal dichalcogenide layers, exhibiting strong optical resonances, will be designed to enhance and control the coupling in an ultrafast 1-30 keV SEM.

Your research will include:

• PINEM and metasurface design (years 1): learn to operate the ultrafast SEM at AMOLF, study PINEM theory and modeling, and design and fabricate metasurfaces in the Amsterdam NanoCenter cleanroom.
• PINEM-metasurface integration (year 2): measure the electron-light interaction of optimized metasurfaces and tailor electron wavepackets by design, including through two subsequent coherent PINEM interactions.
• Coherence and entanglement (year 3-4): investigate correlations between electron energy loss and cathodoluminescence, and test a quantum-eraser geometry in which the which-path information is erased.

The project combines the ultrafast electron-light-matter interaction and cathodoluminescence expertise of Prof. Albert Polman (AMOLF) with metasurface design, fabrication and optical characterization expertise of Dr. Jorik van de Groep (University of Amsterdam). You will be based in the Photonic Materials group of Prof. Polman at AMOLF, with close interaction with the 2D Nanophotonics group of Dr. van de Groep at the University of Amsterdam.

Qualifications
We invite applications from highly motivated candidates with a strong background in physics and a keen interest in nanophotonics, quantum physics, nanofabrication and electron microscopy. We especially encourage individuals from underrepresented groups to apply. Prospective PhD candidates must hold an MSc degree in physics or equivalent qualification.

Work environment
Work environment The Photonic Materials group (www.erbium.nl), led by Prof. Albert Polman, studies light-matter interactions at the nanoscale. The group is composed of an international team of PhD students, postdocs and master students that work in a collaborative atmosphere with many social group activities. Every week we hold a group meeting and departmental colloquium and poster sessions. We also regularly organize an international group labtour.

AMOLF provides state-of-the-art ultrafast electron microscopy systems for time-, angle- and polarization-resolved cathodoluminescence spectroscopy and PINEM, and a shared cleanroom for nanofabrication and characterization (Amsterdam NanoCenter). We offer a highly collaborative and supportive environment, fostering strong connections both within the group and with our national and international partners. PhD students benefit from a variety of courses designed to enhance their research skills.

AMOLF is a part of NWO-I and initiates and performs leading fundamental research on the physics of complex forms of matter, and creates 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 The 2D Nanophotonics lab (https://vandegroeplab.com), led by Dr. Jorik van de Groep, studies nanophotonic metasurfaces that enable active control over light by harnessing the highly tunable optical properties of two-dimensional quantum materials. By combining resonant metallic and semiconductor nanostructures with exciton resonances in 2D semiconductors, we create dynamic metasurfaces that actively tune light emission, scattering, and absorption at the nanoscale. Our group is part of the Institute of Physics at the University of Amsterdam (https://iop.uva.nl) and works in a collaborative atmosphere with other researchers within the department and (inter)national collaborators.

Working conditions

• The working atmosphere at the institute is largely determined by young, enthusiastic, mostly non-Dutch 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 for the duration of four years. The planned start date is December 1, 2026. · The starting salary is 3.115 Euros gross per month and a range of employment benefits.
• After successful completion of the PhD research a PhD degree will be granted at the University of Amsterdam.
• 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 Albert Polman: a.polman@amolf.nl and Jorik van de Groep: j.vandegroep@uva.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).

Commercial activities in response to this ad are not appreciated.

Post-doc position: Emergent computing in nanomechanical oscillator networks

Work Activities
The Mechanical Metamaterials and Hypersmart Matter groups at AMOLF are recruiting a postdoctoral researcher to investigate how interactions between micromechanical oscillators can give rise to unconventional material computers.

You will investigate arrays of coupled silicon drum resonators, each of which can sustain two stable oscillation phases and thereby act as a physical bit. When these bistable elements interact, their collective response can depend on the history and sequence of applied inputs, opening possibilities for memory and computation. Building on ideas developed in macroscopic mechanical metamaterials, you will explore how networks of these microscopic elements can perform tasks such as counting and recognizing input sequences.

You will combine experiments with modelling to uncover the switching pathways of interacting resonators, connect these pathways to computational tasks, and investigate what sets their robustness and energy cost. Tunable interactions and access to multiple vibrational modes provide opportunities to explore how computational behaviour can be reprogrammed within the same physical device. The experiments will take advantage of the state-of-the-art cleanroom at AMOLF, as well as of our optical characterization facilities.

Qualifications
We seek an excellent candidate with a background in physics or engineering, ideally with relevant experience in micromechanics or physical computation. You need to have a doctoral degree, or have met all the requirements and will receive the doctoral degree shortly. We strongly believe in the benefits of an inclusive and diverse workplace, and encourage people from all backgrounds to apply.

Work environment
Our groups create (meta)materials and (meta)devices that process information in novel ways, using phenomena that are not traditionally used for computation. We investigate how computational capabilities emerge from the properties of its physical substrate, such as symmetry, topology and disorder. We aim to challenge the current approach to information processing, which assumes that every computational step is carried out perfectly. Instead, we want to build computers that embrace the complexity and imperfection of real-world physical systems.

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

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 3 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 Marc Serra Garcia: m.serragarcia@amolf.nl and Martin van Hecke: m.v.hecke@amolf.nl.

Application
You can respond to this vacancy online via the button below, at the latest by Nov 30, 2026

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.