Invisibility cloak could be in scientists' line of sight

By CATHERINE CLABBY
Monday, November 13, 2006
Duke University scientists have taken a concrete step toward creating the invisibility cloak they said was theoretically possible back in May. But don't expect to start slipping around unseen a la Harry Potter. The "cloak" _ a rigid new material, not velvety cloth _ diverts microwaves, but not visible light.

Physicist David Schurig, along with Duke engineering professor David R. Smith and English scientists, have designed a material that can steer microwaves around an object. Its performance isn't perfect or practical yet. But it proves that newly engineered materials can be designed in ways once unthinkable.

WHAT IS IT?

Schurig and the others designed a new meta-material in plastic and copper that can move microwaves around an object with little trace that anything was altered.

HOW WILL IT BE USEFUL?

If further developed, such a cloak might be used to hide objects from traditional forms of radar. It might also be used to better focus microwave signals and improve wireless communications.

WHAT MIGHT IT LEAD TO?

Schurig thinks this line of research could one day produce an invisibility cloak _ one that could hide objects from human sight. But that goal poses huge technical problems. Visible light is created by energy waves of extremely tiny lengths. It is not yet possible to design a material that can control such waves and redirect them in the desired way.