Liquid Metal Antenna

A liquid metal antenna can tune over a range of at least two times greater than systems using electronic switches 

Researchers at the North Carolina State University (NCSU) have demonstrated a reconfigurable liquid-metal prototype in the Journal of Applied Physics.

Published in a paper titled by the university, they describe how a reconfigurable liquid metal antenna driven by electrochemically controlled capillarity is a new electrochemical method for reversible, pump-free control of liquid eutectic gallium and indium (EGaIn) in a capillary.

Antennas are interesting as the shape and length of the conducting paths which form them determine their operating frequencies and radiation patterns.

Using a liquid metal – such as eutectic gallium and indium – that can change its shape allows us to modify antenna properties more dramatically than is possible with a fixed conductor,
— Jacob Adams, co-author of the paper and an assistant professor in the Department of Electrical and Computer Engineering at NCSU