Project Leader – QuMat.1-UT-1.1D / 1.2D
QSH devices based on Bi-ene/X materials
QSH devices based on WTe2/X hybrid materials
Co-supervisor – QuMat.1-UT-3.3B
Proximity-induced superconducting and interacting quantum spin/anomalous Hall channels
Brief research summary over last 5 years / academic profile
Alexander Brinkman was appointed as professor in 2011 (youngest UT professor at that time) and he has headed the chair of Quantum Transport in Matter since then. The current focus of his group lies in the quantum transport properties of topological matter, both for electronic as well as quantum computing applications. His experimental team combines state-of-the-art materials science, nanotechnology and cryogenic quantum transport measurements.
New materials are synthesized by combining thin film growth with in-house developed in-situ characterization methods (together with Guus Rijnders and his team at MESA+). Ever since his pioneering work in which magnetic effects were discovered at the interface between non-magnetic oxides (Nature Materials 2007), artificial quantum materials have been a strong focus of his research. For example, in his lab, the first artificial material has been measured in which the quantum and topological properties of Mott vortex lattices can be observed and controlled (Science 2015).
Brinkman’s team realized the world’s first topological Josephson junctions in several classes of topological materials (Nature Materials 2012, Nature Materials 2018). Within the context of his ERC Consolidator Grant, they discovered that Majorana bound states can exist in Dirac semimetals and, together with Forschungszentum Jülich, they developed new technology (selective area growth and stencil lithography) for the observation and manipulation of Majorana states (Nature Nanotechnology 2019).
In 2017, Chuan Li strengthened the team as assistant professor. Since her PhD work in Paris-Sud, she has been regarded as one of the pioneers of superconductivity in higher order topological hinge states. By leading a collaboration with Peking University, she very recently continued this successful work and discovered higher order topological superconductivity in Dirac semimetals (PRL 2020, Nature Communications 2020).
The use of Dirac semimetals in quantum transport experiments has now been extended to study the chiral anomaly and chirality polarization in semimetals. Brinkman’s ongoing NWO Vici project (awarded in 2017) focuses on the observation and control of axion electrodynamics in topological materials, which is relevant for low-power electronics. In addition, the developed topological materials are investigated for quantum energy storage. Industry (Lockheed Martin) is fully funding the latter project (four people for three years).
International visibility, activities, prizes, scholarships etc.
Brinkman is a recognized leader in the fields of superconductivity and topological quantum matter. He serves in international grant review committees and gives on average 5-10 invited talks per year at conferences and academic institutes worldwide. Brinkman is a recipient of NWO Veni, Vidi and Vici grants and an ERC Consolidator grant. He has co-organized international conferences and served as conference chair on 5 occasions. For example, he was chair and initiator of the UK Royal Society meeting on exotic superconductivity, which has generated a very successful and ongoing conference series.
Brinkman has built a strong international network. An example is the recently awarded FET-Open grant on scalable topological quantum bits (University of Twente is coordinator), building on earlier results that were obtained in collaboration with Erik Bakkers. Other collaborations that are relevant for the present proposal is the development of interface technology for topological matter with FZ Jülich (see Nature Nano 2019), the group of Mark Golden at UvA (see Nature Materials 2012 and Nature Materials 2018), and the group of Zhimin Liao in Beijing (PRL 2019, PRL 2020, Nature Communications 2020).
Brinkman was elected to the young academy (DJA) of the royal Dutch academy of sciences (KNAW). He is active in the field of outreach and science policy. Besides public lectures on national television and at major pop festivals, he was chair of the jury of natural sciences for the National Science Agenda (NWA). The large number of research questions from the general public has led to an increase in science funding.
Another field of societal involvement is the area of education. Being a passionate and enthusiastic teacher himself (awarded with the “Best teacher of the University of Twente” prize), Brinkman has become involved in the didactics of physics at university and higher education. He has been promoter of one PhD student in this field and has co-authored international publications on the didactics of quantum mechanics. These results are now being used for the development of the national curriculum of higher education.
5 key output/publications
Magnetic effects at the interface between nonmagnetic oxides.
A. Brinkman, M. Huijben, M. van Zalk, J. Huijben, U. Zeitler, J.C. Maan, W.G. van der Wiel, G. Rijnders, D.H.A. Blank, and H. Hilgenkamp, Nature Materials 6, 493 (2007).
We discovered that magnetism can exist at an interface between non-magnetic materials. This article is cited > 1000 times and was announced by Thomson Reuters (Science Watch, Jan. 2009) as most Hot Paper in Materials Science.
Critical behavior at a dynamic vortex insulator-to-metal transition.
N. Poccia, T.I. Baturina, F. Coneri, C.G. Molenaar, X.R. Wang, G. Bianconi, A. Brinkman, H. Hilgenkamp, A.A. Golubov, and V.M. Vinokur, Science 349, 1202 (2015).
We have realized and measured an artificial quantum material based on a Josephson array. By tuning the magnetic field through the Josephson array, we can effectively tune the electron density per atom. In this first study we have proven the analogy by looking at the Mott metal-insulator transition, driven by current.
4pi periodic Andreev bound states in a Dirac semimetal.
C. Li, J. de Boer, B. de Ronde, S.V. Ramankutty, E. van Heumen, Y. Huang, A. de Visser, A.A. Golubov, M.S. Golden, and A. Brinkman, Nature Materials 17, 875 (2018).
Using crystals from a collaboration with the university of Amsterdam, our team discovered that Majorana bound states can also exist in Dirac semimetals, thereby opening up a whole new field of topological superconductivity.
Selective area growth and stencil lithography for in situ fabricated quantum devices.
P. Schüffelgen, D. Rosenbach, C. Li, T.W. Schmitt, M. Schleenvoigt, A.R. Jalil, S. Schmitt, J. Kölzer, M. Wang, B. Bennemann, U. Parlak, L. Kibkalo, S. Trellenkamp, T. Grap, D. Meertens, M. Luysberg, G. Mussler, E. Berenschot, N. Tas, A.A. Golubov, A. Brinkman, T. Schäpers, and D. Grützmacher, Nature Nanotechnology 14, 825 (2019).
This collaboration with the FZ Jülich is a good example how developments in materials science (stecil lithography as well as selective area growth) have led to technology, which the accompanying News&Views article referred to as a “Majorana mass production line”.
Reducing Electronic Transport Dimension to Topological Hinge States by Increasing Geometry Size of Dirac Semimetal Josephson Junctions.
C. Li, A. Wang, C. Li, W. Zheng, A. Brinkman, D. Yu, and Z. Liao, Physical Review Letters 124, 156601 (2020).
First experimental realization of superconductivity in the higher order topological hinge states of a Dirac semimetal. The paper reflects a fruitful collaboration between our team and Peking University.