How To Use Computers Heat To Generate Electricity

Electronic devices such as computers generate heat that mostly goes to waste. Physicists at Bielefeld University (Germany) have found a way to use this energy: They apply the heat to generate magnetic signals known as ‘spin currents’. In future, these signals could replace some of the electrical current in electronic components. In a new study, the physicists tested which materials can generate this spin current most effectively from heat. The research was carried out in cooperation with colleagues from the University of Greifswald, Gießen University, and the Leibniz Institute for Solid State and Materials Research in Dresden.

The Bielefeld physicists are working on the basic principles for making data processing more effective and energy-efficient in the young field of ‘spin caloritronics’. They are members of the ‘Thin Films & Physics of Nanostructures’ research group headed by Professor Dr. Günter Reiss. Their new study determines the strength of the spin current for various combinations of thin films.

A spin current is produced by differences in temperature between two ends of an electronic component. These components are extremely small and only one millionth of a millimetre thick. Because they are composed of magnetic materials such as iron, cobalt, or nickel, they are called magnetic nanostructures.

The physicists take two such nanofilms and place a layer of metal oxide between them that is only a few atoms thick. They heat up one of the external films – for example, with a hot nanowire or a focused laser. Electrons with a specific spin orientation then pass through the metal oxide. This produces the spin current. A spin can be conceived as electrons spinning on their own axes – either clockwise or anti-clockwise.

Their findings have been  published  in the research journal ‘Nature Communications’.


Car, Boat, Airplane: Bye Bye Sickness

The misery of motion sickness could be ended within five to ten years thanks to a new treatment being developed by scientists. The cause of motion sickness is still a mystery but a popular theory among scientists says it is to do with confusing messages received by our brains from both our ears and eyes, when we are moving. It is a very common complaint and has the potential to affect all of us, meaning we get a bit queasy on boats or rollercoasters. However, around three in ten people experience hard-to-bear motion sickness symptoms, such as dizziness, severe nausea, cold sweats, and more.

Research from Imperial College London, published today (4 September) in the journal Neurology, shows that a mild electrical current applied to the scalp can dampen responses in an area of the brain that is responsible for processing motion signals. Doing this helps the brain reduce the impact of the confusing inputs it is receiving and so prevents the problem that causes the symptoms of motion sickness. This technique offers a safe and effective intervention that is likely to be available for anyone to buy, in the future.


We are confident that within five to ten years people will be able to walk into the chemist and buy an anti-seasickness device. It may be something like a tens machine that is used for back pain”, said Dr Qadeer Arshad from the Department of Medicine at Imperial College London who led the research. “We hope it might even integrate with a mobile phone, which would be able to deliver the small amount of electricity required via the headphone jack. In either case, you would temporarily attach small electrodes to your scalp before travelling – on a cross channel ferry, for example.