Introduction to the fifth special issue on nanoelectronic circuits

This special issue is already the fifth one in a series on nanoelectronic circuits. It follows Special Issues published in 2000/2001 (Vol. 28, Issue 6 and Vol. 29 Issue 1), in early 2003 (Vol. 31 Issue 1), in late 2004 (Vol. 32 Issue 5), and in 2007 (Vol. 35 Issue 3). A decade ago the emerging nanotechnology was a hopeful newcomer in electronic engineering laboratories. Discoveries in physics and chemistry provided an arsenal of instruments, tools, and microscopes; thus, the fabrication and characterization of nanoscale artifacts became feasible. Many circuit engineers shared great hopes that by the end of the decade circuits composed of nanoscale devices, such as nanoscale transistors, resonant tunneling devices, and circuits composed of single electron devices could take their share on the market of ultra large scale integrated circuits as memories and processors. As fabrication and characterization tools with feature sizes even below 10 nm approaches the molecular scale, quantum phenomena become dominant sway, quantum superposition, tunneling and entanglement open the road to engineering applications, such as quantum computing and cryptography. The decade is over, and many hopeful engineering applications are lagging behind.