Most people were probably unaware the heat and sound have much in common and that it is possible to control heat—and probably sound – with magnetic fields. However, Ohio State researchers just published an article in Nature Materials in which they discuss their experiments where in they were able to reduce the amount of heat traveling through a semiconductor by 12 percent using a magnetic field about the size of a medical MRI. This is the first study to demonstrate that acoustic phonons, which are the particles that transmit both heat and sound, have magnetic properties.
Researchers believe with a strong enough magnetic field they should be able to control sound waves as well as heat.
At the moment it is difficult for researchers to imagine practical applications because the experiments were difficult to set up and the equipment doesn’t exist outside of hospitals and research laboratories. However, the discovery is interesting; theoretically one would be able to control the temperature materials like plastics, stone and glass with a strong enough magnet. In metals the difference would be negligible because so much heat is carried via electrons researchers say.
The next experiment these researchers have in mind is to see if they can deflect sound waves sideways with a magnetic field.