Experimental physicist Jan Aarts has been awarded a FOM Projectruimte grant of 545.000 euro. He will use the money to research the interplay between superconducting currents and ferromagnetism. In the future this could lead to computer memory with negligible power More info
One of many ways for computers to store their memory is with the use of ferromagnets. They read and write data by flipping small ferromagnets using electric currents. Inevitably, this goes hand in hand with the loss of energy. Except of course if these ferromagnets are superconducting and let currents flow without any resistance. Physicist Jan Aarts and his team already showed that this is possible by growing layers of the ferromagnet chromium dioxide and inducing so-called supercurrents. However, to use this in real-life computers, thin but wide layers are not useful.
In a recent development, the team learned how to grow wires instead of layers. With the FOM Projectruimte grant, Aarts is now able to hire a PhD student and a postdoc and purchase new equipment, so that he can research supercurrents through chromium dioxide devices based on wires. By studying the interplay between superconductivity and ferromagnetism, he aims to lay the groundwork for future applications, like solid state drives that read and write data without loss of power. Aarts’ research group is at the moment the only group in this research field with the skills to fabricate the necessary wires, giving them a head start on their mission.
Electron microscope image of a chromium dioxide devices based on wires. The green wire is the chromium dioxide ferromagnet. The orange wires are superconductors and are necessary to produce a superconducting current through the green wire.
Vasyl Palchykov from the Lorentz Institute will give an LCN2 seminar on May 27th at 16:00 in room HL214, titled 'Ground truth? Clustering scientific publications'.
Community detection techniques are widely used to infer hidden structures within interconnected systems. More info
Despite demonstrating high accuracy on benchmarks, they reproduce the external classification for many real-world systems with a significant level of discrepancy. A widely accepted reason behind such outcome is the unavoidable loss of non-topological information (such as node attributes) encountered when the original complex system is represented as a network.
In this talk we will show that the observed discrepancies may also be caused by a different reason: the external classification itself. For this end we use scientific publication data, which i) exhibit a well defined modular structure and ii) hold an expert-made classification of research articles. Having represented the articles and the extracted scientific concepts both as a bipartite network and as its unipartite projection, we applied modularity optimization to uncover the inner thematic structure. The resulting clusters are shown to partly reflect the author-made classification, although some significant discrepancies are observed. A detailed analysis of these discrepancies shows that they carry essential information about the system, mainly related to the use of similar techniques and methods across different (sub)disciplines, that is otherwise omitted when only the external classification is considered.
Physicist Luca Giomi has been awarded an NWO Vidi grant of 800,000 euro to theoretically investigate artificial cell-like structures. This year, a total of 572 researchers applied for a Vidi. Only 87 of them have been granted funds, including twelve More info
from Leiden University.
The goal of the Giomi’s research is to theoretically investigate an artificial cell-like structure to understand how mechanical functionality emerges in living matter. Living cells are capable of astonishing mechanical functionalities. They can deform spontaneously or, in response to environmental stimuli, move in a fluid or on a substrate and generate enough force to split themselves in two, while remaining alive. These unique properties are possible because the building blocks that form the mechanical apparatus of the cell are active: they are able to transform stored or ambient energy into mechanical work.
But how does functionality emerge from mechanical activity? In order to address this question, Giomi will focus on an artificial cell-like structure consisting of a lipid vesicle enclosing an active liquid crystal that performs the functions of the cytoskeleton. Using this active prototype cell as a model system, he will shed light on the complex mechanical properties that characterize the “fabric of life”.
As part of the master course 'Academic and Professional Skills', four physics master students have created a video about Sense Jan van der Molen's research group. Jamie Culkin, Anne Meeussen, Sander van Lidth de Jeude and Isabelle Jansen devised the More info
project from scratch and started a collaboration with filmmaker Nestor Romero Clemente.
Jan van Ruitenbeek (2016) Molecular machines and devices, Beilstein Journal, 7, 310-311. [DOI][pdf]
Waqqar Ahmed1,Jan M. van Ruitenbeek (2016) One-step Synthesis of Cetyltrimethylammonium Bromide Stabilized Spherical Gold Nanoparticles, Journal of Nanoscience with Advanced Technology, 1(3), 20-24. [Abstract][DOI][pdf]
24 May, 11:30, Casimir room, Oort building
Theory seminar Dirk K. Morr, University of Illinois at Chicago: Charge Transport as a Probe for Topological Superconductors
24 May, 13:45, De Sitterzaal, room 032, Oortbuilding
Lecture Course Lorentz Professor Prof. Ch. L. Kane: “Symmetry, Topology and Phases of Matter” "Topological Superconductivity"
26 May, 16:00, GL - Cell Observatory
van Leeuwenhoek lecture on BioScience Doyne Farmer (Oxford, Mathematics and Complexity Economics): The Evolution of Technology Abstract