Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Magnetic Stirrer Levitation: The Flight of the Humble Flea

08.08.2018

Göttingen Max Planck scientist discovers an entirely new method of levitation

The idea of levitation has inspired technology such as Maglev trains, and innumerable works of fiction, like hover-boards from the „Back to the Future“ trilogy or even a common image of a witch flying on her broomstick over a sleeping village.


Top: Image of the levitating flea in Castor Oil. Bottom: A 3D spiral rendered by combining experimental images of the flea over a 1 s period.

However, most real-world applications require either highly specialized equipment, or sub-zero temperatures, which makes them not easily practicable in our everyday life. Here, a researcher from the Max Planck Institute for Dynamics and Self-organization (MPIDS) demonstrates a ground-breaking approach that will make magnetic levitation more accessible to a wider range of technical applications.

The new method uses a simple tool that most laboratories world-wide already possess: a magnetic stirrer, a device that employs a rotating magnetic field to cause a stirring bar immersed in a liquid to spin very quickly, thus mixing it.

Since its invention in 1942, it has been known that if such a stirrer is driven too quickly, the stirring bar-magnet will hop erratically on the base of the container – hence its nickname „the flea“. MPIDS scientist Dr. Kyle Baldwin finds that if the viscosity of the liquid in a container is similar to that of honey, the flea stops hopping and instead jumps up and levitates within the liquid.

„We stumbled upon this phenomenon whilst mixing high viscosity polymer solutions, and were fascinated,“ recalls Kyle, the first author of the paper. Alongside researchers from Nottingham, Kyle carefully analyzed the motion of the levitating flea in a large series of experiments and found that its motion is systematic.

The stirring bar waggles back-and-forth, pumping fluid out to the sides, which experiment and simulations show stabilizes its position. Intriguingly, if the viscosity is reduced, the fluid is pumped in the opposite direction, and the flea falls.

„Our discovery should motivate the design of bi-directional fluidic pumps, improve understanding of effective swimming methods, and provide a new levitation route for container-less storage or friction-less transport", explains Dr. Baldwin.

This fundamental discovery could be used in robotics and provide new opportunities in nano-technology and medicine, such as providing easily controllable artificial micro swimmers for a better diagnostic. New horizons that are being opened by the discovery are truly breath taking! However, it is still unlikely to make flying broomsticks a reality.

Originalpublikation:

https://journals.aps.org/prl/accepted/43075Y94Afb11f5534792c45ecaa8e6270ea7376a

Carolin Hoffrogge | Max-Planck-Institut für Dynamik und Selbstorganisation
Further information:
http://www.ds.mpg.de/

More articles from Physics and Astronomy:

nachricht The taming of the light screw
22.03.2019 | Max-Planck-Institut für Struktur und Dynamik der Materie

nachricht Magnetic micro-boats
21.03.2019 | Max-Planck-Institut für Polymerforschung

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Eliminating hepatitis C viruses effectively

25.03.2019 | Life Sciences

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>