With leading research into fundamental physics, we can answer important questions about the world of today and tomorrow. This requires curious individuals who want to push the experimental boundaries of science with their talent and expertise. As a PhD Candidate at the Scanning Probe Microscopy department, you get to explore the future of brain-inspired computing with our state-of-the-art facilities.

The goal of this PhD project is to explore bottom-up atomic spin systems to understand multi-well energy landscapes and their use for brain-inspired computing.

One of the paradigms in brain-inspired computing is based on creating attractor networks, where metastable local minima are used to represent information. In physics, such multi-well landscapes can be created from glassy spin systems, which exhibit metastable order. In 2020 (1), we hypothesised that atomic arrays of spins can be used to create such multi-well landscapes by using long-range interactions that lead to frustration. In 2020, we made the first observation of a magnetic system that exhibits a related so-called self-induced spin glass state, in elemental Nd (2). At the same time, we found that atomic systems can also exhibit multi-well behaviour (3). Using the concept of orbital memory as we experimentally observed in 2018 (4), we showed that arrays of Co atoms can be used to create a Boltzmann machine, in which the stochastic dynamics of arrays of Co atoms can be used to present neurons and synapses in this model. We have continued to study the physical origins of orbital memory, and its manifestation in other atomic systems (5-6).

Relevant references:
(1) A. Kolmus, M. I. Katsnelson, A. A. Khajetoorians, H. J. Kappen, Atom-by-atom construction of attractors in a tunable finite size spin array. New Journal of Physics 22, 023038 (2020).
(2) U. Kamber et al., Self-induced spin glass state in elemental and crystalline neodymium. Science 368, eaay6757 (2020).
3) B. Kiraly, E. J. Knol, W. M. J. van Weerdenburg, H. J. Kappen, A. A. Khajetoorians, An atomic Boltzmann machine capable of self-adaption. Nature Nanotechnology 16, 414-420 (2021).
(4) B. Kiraly et al., An orbitally derived single-atom magnetic memory. Nature Communications 9, 3904 (2018).
(5) B. Kiraly, E. J. Knol, A. N. Rudenko, M. I. Katsnelson, A. A. Khajetoorians, Orbital memory from individual Fe atoms on black phosphorus. Physical Review Research 4, 033047 (2022).
(6) E. J. Knol et al., Gating Orbital Memory with an Atomic Donor. Physical Review Letters 128, 106801 (2022).

We have in total 2 positions available. Your teaching load may be up to 10% of your working time.

• You have a Master’s degree in physics and completed a Master’s thesis on an experimental research topic.
• You have a good command of oral and written English.
• You are open to further develop your scientific communication skills through presentations and publications.
• You have a strong interest in condensed matter physics.

Fixed-term contract: You will be employed for an initial period of 18 months, after which your performance will be evaluated. If the evaluation is positive, the contract will be extended by 2.5 years (4 year contract).

• It concerns an employment for 1.0 FTE.
• The gross starting salary amounts to €2,541 per month based on a 38-hour working week, and will increase to €3,247 in the fourth year (salary scale P). 
• You will receive 8% holiday allowance and 8.3% end-of-year bonus.
• You will be employed for an initial period of 18 months, after which your performance will be evaluated. If the evaluation is positive, the contract will be extended by 2.5 years (4 year contract).
• You will be able to use our Dual Career and Family Care Services. Our Dual Career and Family Care Officer can assist you with family-related support, help your partner or spouse prepare for the local labour market, provide customized support in their search for employment and help your family settle in Nijmegen.
• Working for us means getting extra days off. In case of full-time employment, you can choose between 30 or 41 days of annual leave instead of the legally allotted 20.

Work and science require good employment practices. This is reflected in Radboud University's primary and secondary employment conditions. You can make arrangements for the best possible work-life balance with flexible working hours, various leave arrangements and working from home. You are also able to compose part of your employment conditions yourself, for example, exchange income for extra leave days and receive a reimbursement for your sports subscription. And of course, we offer a good pension plan. You are given plenty of room and responsibility to develop your talents and realise your ambitions. Therefore, we provide various training and development schemes.

You will join the Scanning Probe Microscopy department (SPM) and also contribute to the department of Ultrafast Spectroscopy of Correlated Materials at the Institute for Molecules and Materials (IMM), which is one of the major research institutes of the Faculty of Science at Radboud University. IMM is a research institute in chemistry and physics, which fosters interdisciplinary research. Its mission is to design and create functional molecules and materials to fundamentally understand their behaviour. The institute comprises 19 research groups in areas ranging from condensed matter science to organic chemistry and biochemistry. IMM focuses on fundamental research with an open eye for societal applications and educates the next generation of leaders in science and innovation. IMM distinguishes itself from similar institutes by close collaborations and rich interactions between chemists and physicists and/or experimentalists and theorists, and an excellent infrastructure including the Scanning Probe Laboratories, Laser Labs, Magnetic Resonance Research Centre, High Field Magnet Laboratory, and Free Electron Laser Laboratory (HFML-FELIX).

The SPM department consists of many international scientists and students. We host world-class SPM instruments and utilise SPM techniques beyond the state of the art to study numerous problems in fundamental physics and chemistry. Our expertise focuses on high precision magnetic and electronic imaging of single atoms, molecules and surfaces in cryogenic ultrahigh vacuum environments and in magnetic fields, often related with single-atom manipulation.

The Faculty of Science is a complete, student-oriented science faculty where research and education are closely intertwined. The faculty aims to form an academic community with an international character, where staff members from different backgrounds can combine their talents with the common goal of being among the leading science faculties in Europe.



Radboud University

We want to get the best out of science, others and ourselves. Why? Because this is what the world around us desperately needs. Leading research and education make an indispensable contribution to a healthy, free world with equal opportunities for all. This is what unites the more than 24,000 students and 5,600 employees at Radboud University. And this requires even more talent, collaboration and lifelong learning. You have a part to play!