s about five times larger than the original but still SO small that its shape can only be seen in a microscope. Its strings are really silicon bars, 150 by 200 nm in cross-section and ranging from 6 to 12 um in length (a micrometer is one-millionth of a meter; a nanometer is a billionth of a meter, the length of three silicon atoms in a row). The strings vibrate at frequencies 17 octaves higher than those of a real guitar, or about 130,000 times higher. The researchers recently observed that light from a laser could cause prop- erly designed small devices to oscillate, and this effect underlies the nano- guitar design. The nanoguitar is played by hitting the strings with a focused laser beam. When the strings vibrate, they create interference patterns in the light reflected back, which can be detected and electronically converted down to audible notes. The device can play only simple tones, although chords can be played by activating more than one string at a time. The pitches of the strings are determined by their length, not by their tension as in a normal guitar, but the group has "tuned" the resonances in similar devices by apply- ing a direct current voltage. "The generations of researchers to come can aim to play more complex pieces," says Sekaric. "This goal would indeed improve the science and tech- nology of NEMS by aiming for integrated driving and detection schemes as well as a wide range of frequencies produced from a small set of vibrating elements." Most of the devices the group studies don't resemble guitars, but the study of resonances often leads to musical analogies, and the natural designs of the small resonant systems often leads to shapes that look like harps, xylophones, or drums. The guitar shape was, Craighead Sekaric says, "an artistic expression by the engineering students." Sekaric notes that "a nanoguitar, as something close to almost everybody's understanding and experience, can also be used as a good educational tool about the field of nanotechnology, which indeed needs much public e