Contents

25 May 2012
Vol 336, Issue 6084

About The Cover

Cover image expansion

COVER Artist's rendering of an electronic device hosting Majorana fermions. The semiconducting nanowire (cylindrical structure) has a diameter of 100 nanometers and lies atop a gate structure consisting of many metallic stripes. The nanowire is contacted at the top with a gold electrode and at the bottom with a superconducting electrode (shown in blue). See page 1003. Image: V. Mourik, K. Zuo, S. M. Frolov, S. R. Plissard, E. P. A. M. Bakkers, L. P. Kouwenhoven, with assistance from www.avalondesigns.nl. [View this image side-by-side with a scanning electron microscope (SEM) image of the same perspective.]