Carbon nanotubes and graphene are both made up of carbon and have unique properties. Graphene comprises an atom-thick layer of carbon atoms, while carbon nanotubes can be likened to a graphene sheet that has been rolled up to form a tube.
"If you stretch a graphene sheet from end to end the thin layer can oscillate at a basic frequency of getting on for a billion times a second," says researcher Anders Nordenfelt. "This is the same frequency range used by radios, mobile phones and computers."Possible to weigh DNA molecules
In addition to new applications in electronics, research is under way into how graphene can be used to weigh extremely small objects such as DNA molecules.Self-oscillating nanowires
"The question is whether they can also be used to produce this type of signal in a controlled and effective way," says Anders Nordenfelt. "This assumes that they themselves are not driven by an oscillating signal that, in turn, needs to be produced by something else."
In his research Anders Nordenfelt carried out a mathematical analysis to demonstrate that it is possible to connect the nanowire with a fairly simple electronic circuit, and at the same time to apply a magnetic field and thus get the nanowire to self-oscillate mechanically.
"At the same time we're converting a direct current to an alternating current with the same frequency as the mechanical oscillation," says Anders Nordenfelt.Harmonics – a way of reaching even higher frequencies
"An unexpected and very interesting result is that the method I've proposed can be used to get the nanowire to self-oscillate in one of its harmonics," says Anders Nordenfelt. "You can change the harmonic by altering the size of one or more of the electronic components."In principle, there are an infinite number of harmonics with unlimited high frequencies, but there are practical limitations.
This area is particularly interesting as it lies on the boundary between microwaves and infrared radiation that, to date, has been the subject of relatively little research. It is an area that has been too fast for electronic circuits, but too slow for optical circuits.
"We can't get these really high frequencies with my method as things stand, but it could be something for the future," says Anders Nordenfelt.
The thesis has been successfully defended.For more information, please contact: Anders Nordenfelt
Software for diagnostics and fail-safe operation of robots developed at FEFU
23.08.2019 | Far Eastern Federal University
New tools to minimize risks in shared, augmented-reality environments
21.08.2019 | University of Washington
Since their experimental discovery, magnetic skyrmions - tiny magnetic knots - have moved into the focus of research. Scientists from Hamburg and Kiel have now been able to show that individual magnetic skyrmions with a diameter of only a few nanometres can be stabilised in magnetic metal films even without an external magnetic field. They report on their discovery in the journal Nature Communications.
The existence of magnetic skyrmions as particle-like objects was predicted 30 years ago by theoretical physicists, but could only be proven experimentally in...
Theoretical physicists at Trinity College Dublin are among an international collaboration that has built the world's smallest engine - which, as a single calcium ion, is approximately ten billion times smaller than a car engine.
Work performed by Professor John Goold's QuSys group in Trinity's School of Physics describes the science behind this tiny motor.
Together with the University of Innsbruck, the ETH Zurich and Interactive Fully Electrical Vehicles SRL, Infineon Austria is researching specific questions on the commercial use of quantum computers. With new innovations in design and manufacturing, the partners from universities and industry want to develop affordable components for quantum computers.
Ion traps have proven to be a very successful technology for the control and manipulation of quantum particles. Today, they form the heart of the first...
Experimental progress towards engineering quantized gauge fields coupled to ultracold matter promises a versatile platform to tackle problems ranging from condensed-matter to high-energy physics
The interaction between fields and matter is a recurring theme throughout physics. Classical cases such as the trajectories of one celestial body moving in the...
Soft robots have a distinct advantage over their rigid forebears: they can adapt to complex environments, handle fragile objects and interact safely with humans. Made from silicone, rubber or other stretchable polymers, they are ideal for use in rehabilitation exoskeletons and robotic clothing. Soft bio-inspired robots could one day be deployed to explore remote or dangerous environments.
Most soft robots are actuated by rigid, noisy pumps that push fluids into the machines' moving parts. Because they are connected to these bulky pumps by tubes,...
16.08.2019 | Event News
14.08.2019 | Event News
12.08.2019 | Event News
23.08.2019 | Life Sciences
23.08.2019 | Information Technology
23.08.2019 | Life Sciences