Submarines need to probe ocean depths, and that too without being visible to enemies at times - both properties that they can now implement using new nanotube technology.

Speakers made from carbon nanotube sheets that are a fraction of the width of a human hair can both generate sound and cancel out noise - properties conducive to submarine technology.

Ali Aliev and colleagues explain that every time that an electrical pulse passes through the microscopic layer of carbon tubes, the air around them heats up and creates a sound wave.

Although Chinese nanoscientists were already aware of this property they did not test its ability to operate under water.

Aliev's group took that step, showing that nanotube sheets produce the kind of low-frequency sound waves that enable sonar to determine the location, depth, and speed of underwater objects.

They also verified that the speakers could be tuned to specific frequencies to cancel out noise, such as the sound of a submarine moving through the depths.

The study appears in appears in ACS' Nano Letters. (ANI)