Submarines could use new nanotube technology for sonar and stealth

Jul 14, 2010
Submarines of the future could be equipped with “nanotube speakers” to help improve sonar to probe the ocean depths and make the vessels invisible to enemies. Credit: iStock

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 ideal for submarine sonar to probe the ocean depths and make subs invisible to enemies. That's the topic of a report on these "nanotube speakers," which appears in ACS' Nano Letters.

Ali Aliev and colleagues explain that thin films of nanotubes can generate sound waves via a thermoacoustic effect. Every time that an electrical pulse passes through the microscopic layer of carbon tubes, the air around them heats up and creates a .

Chinese scientists first discovered that effect in 2008, and applied it in building flexible speakers. In a remarkable demonstration, which made its way onto YouTube, the Chinese nanoscientists stuck a sheet of nanotubes onto the side of a flag, and attached it to an mp3 player. They used the nanotube-coated flag to play a song while it flapped in the breeze. But 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 can be tuned to specific frequencies to cancel out noise, such as the sound of a submarine moving through the depths.

Explore further: Nanoscale production line for the assembly of biological molecules

More information: "Underwater Sound Generation Using Carbon Nanotube Projectors", Nano Letters.

Related Stories

Nanotech Speakers Hold Promise for Sonar Uses

Jun 14, 2010

(PhysOrg.com) -- UT Dallas researchers have found that carbon nanotube sheets perform well as underwater sound generators and noise-canceling speakers, two highly desirable traits for submarine sonar and stealth ...

Tiny Music Player Made from Wire Bridge (w/ Video)

Nov 04, 2009

(PhysOrg.com) -- In 2008, scientists built a loudspeaker made of carbon nanotubes that produced sound and music based on the thermoacoustic effect. Now, a different team of scientists has built a loudspeaker ...

Diamonds key to a sparkling listening experience

Feb 18, 2005

Music lovers could be in for the ultimate listening experience, thanks to a new range of speakers containing parts made of diamond, writes Marina Murphy in the Chemistry & Industry magazine. The unique properties of diamond ...

Recommended for you

Biomimetic photodetector 'sees' in color

Aug 25, 2014

(Phys.org) —Rice University researchers have created a CMOS-compatible, biomimetic color photodetector that directly responds to red, green and blue light in much the same way the human eye does.

User comments : 0