Scientists at the University of Texas have successfully created a nano cloaking device using Carbon Nano Tubes (CNT’s) to make objects disappear underwater adapting the “Mirage Effect”. The researchers used one molecule thick CNT’s sheets wrapped in cylindrical tubes to show that the objects can be made to disappear.
The interesting feature of this device is that it also can be activated and deactivated as and when required. This feature is best utilized underwater.
The mirage effect is an optical illusion, in which light rays bend producing a displaced image of an object that is far from the observer. Classic example would be that an observer would see pools of water at a distant horizon in the ground. This is mainly caused due to the fact that the air nearer to the surface of the ground is warmer than the air above it causing the light rays to bend upward towards the observer’s eyes instead of reflecting off the surface. The image is the reflection of the sky that tends to appear like water on the ground, which in turn is the reflected image of the sky as the observer’s brain perceives it to be so.
The CNT’s properties are special with density that of the air and strong as steel with particularly its ability to conduct and dissipate heat to the surrounding environment made it an ideal material for this cloaking device. Through electricity these clear CNT sheets are heated to very high temperatures. Their heat dissipation property lets the heat generated be transferred to the surrounding environment causing the light to bend thereby cloaking the object they are wrapped around, making the objects to disappear.
Source: http://www.iop.org