Metamaterials could improve wireless power transmission

May 24, 2011

Electrical engineers at Duke University have determined that it is theoretically possible to improve the efficiency of recharging devices without wires, using metamaterials.

Normally, as power passes from a transmitting device to a receiving device, most (if not all) of it scatters and dissipates unless the two devices are extremely close together. The metamaterial postulated by the researchers, which would be situated between the energy source and the “recipient” device, greatly refocuses the transmitted energy for minimal loss of power.

The metamaterial used in the wireless power transmission would likely be made of hundreds to thousands — depending on the application — of individual thin conducting loops arranged into an array. Each piece is made from the same copper-on-fiberglass substrate used in printed circuit boards, with excess copper etched away. These pieces can then be arranged in an almost infinite variety of configurations.

‘The system would need to be tailored to the specific recipient device, in essence the source and target would need to be ‘tuned’ to each other,” says Yaroslav Urzhumov. “This new understanding of how matematerials can be fabricated and arranged should help make the design of wireless power transmission systems more focused.”

Yaroslav Urzhumov, David Smith, Metamaterial-enhanced coupling between magnetic dipoles for efficient wireless power transfer, Physical Review B, 2011; 83 (20) DOI: 10.1103/PhysRevB.83.205114