Physicists from Cornell University demonstrate time cloaking device

You might have seen it happen in science fiction movies, but time cloaking is not just a concept. Scientists in the past have been able to demonstrate time cloaking in their labs. It needs a medium in which time can be sped up or slowed down. The basic concept in time cloaking involves speeding up the leading part of light while slowing down the trailing part. As a result, the leading part reaches at the point of occurrence before time, while the trailing part arrives late. The observer only sees a continuous stream of light and misses the event.

Temporal cloaking

Brainchild:

This time it is the physicists from Cornell University who have demonstrated a time cloaking device that can create a time lag of up to 15 trillionths of a second. The team consisted of Moti Fridman and his colleague physicists. The scientists were able to compress and decompress light, passing it through an optical fiber. This creates a lag between the two waves, thereby resulting in a void.

The making:

Light is passed through an optical cable. A pair of silicon lens is used inside the optical cable in this setting. While one silicon lens is used to speed up and slow down the light waves, the other is used to assemble them together. It is the occurrence of an event within the spacing of these lenses that goes unnoticed. However, the light that comes out of the cable is unaltered.

Time cloaking device

What’s new:

Cloaking devices have been designed before using mirrors that work by bending light around the object. The electromagnetic waves are guided around the object without the object reflecting any of the waves. This results in the observer remaining aloof of existence of any such object. However, this cloaking device works by compressing light. A special type of silicon lens has been employed for this purpose within the optical cable.

What's refreshing:

This is a scaled up version of all invisibility cloaks that have been introduced before. Previously meta-materials have been used to create such cloaking devices. In this case meta-materials have been substituted by silicon lens and this has led to increase in size of objects that can be hidden. The increase in size of cloaked area will eventually make this technology useful in applications such as signal processing.

Applications:

The technology can be used in computing applications especially signal processing. It could be used to interrupt processing on a particular data channel while diverting resources to another channel. An uninterrupted original signal can be reproduced at the other end. It can be used by military to hide coded messages between such cloaks which would make them imperceptible. It can also be used to intercept crucial data without any record of any such activity.

However, the scientists believe that the period of such happening cannot be extended beyond 120 microseconds, which limits the scope of applications of this technology.