21 March 2003
Vol 299, Issue 5614

About The Cover

Cover image expansion

COVER Atomically resolved scanning tunneling microscope images show that silicon nanowires with diameters as small as 1.3 nanometers (the uppermost wire) maintain regular ordered crystalline structure. However, the electronic band gap increases as the nanowire diameter decreases, revealing a remarkable quantum size effect, as described on page 1874. [Image: D. D. D. Ma et al.]