Imagine tiny ears listening for whispers of microscopic life on Mars or rustlings of cells within the body.
To create microphones more sensitive than any available today, a team of researchers is developing devices that resemble the microscopic, supersensitive hairs, or stereocilia, of the inner ear. The devices rely on structures that are even more responsive than stereocilia, which bend a few nanometers at the sound of rustling leaves, says Flavio Noca of NASA's Jet Propulsion Laboratory in Pasadena, Calif.
Noca and his colleagues are working with arrays of carbon nanotubes—hollow tubes of carbon, each one only several atom-widths in diameter. Noca described the research Dec. 5 at the joint meeting of the Acoustical Soci