Spintronics--Science American.com. 2002.6 　

FEATURE ARTICLE 
June 2002 issue 
Spintronics
Microelectronic devices that function by using the spin of the electron are 
a nascent multibillion-dollar industry--and may lead to quantum microchips
By David D. Awschalom, Michael E. Flatté and Nitin Samarth 

The Author(s):
David D. Awschalom, Michael E. Flatté and Nitin Samarth began working as a 
team when Flatté was recently on sabbatical at the University of 
California, Santa Barbara. Awschalom and Samarth had already been 
collaborating on experimental studies of semiconductor spintronics for more 
than a decade. Awschalom is professor of physics and director of the Center 
for Spintronics and Quantum Computation at U.C.S.B. Flatté works on 
condensed-matter theory and is associate professor at the University of 
Iowa. Samarth is professor of physics at Pennsylvania State University.


As rapid progress in the miniaturization of semiconductor electronic 
devices leads toward chip features smaller than 100 nanometers in size, 
device engineers and physicists are inevitably faced with the looming 
presence of quantum mechanics--that counterintuitive and sometimes 
mysterious realm of physics wherein wavelike properties dominate the 
behavior of electrons. Pragmatists in the semiconductor device world are 
busy conjuring up ingenious ways to avoid the quantum world by redesigning 
the semiconductor chip within the context of "classical" electronics [see 
"A Vertical Leap for Microchips," by Thomas H. Lee; Scientific American, 
January]. Yet some of us believe that we are being offered an unprecedented 
opportunity to define a radically new class of device that would exploit 
the idiosyncrasies of the quantum world to provide unique advantages over 
existing information technologies.
One such idiosyncrasy is a quantum property of the electron known as spin, 
which is closely related to magnetism. Devices that rely on an electron's 
spin to perform their functions form the foundation of spintronics (short 
for spin-based electronics), also known as magnetoelectronics. 
Information-processing technology has thus far relied on purely 
charge-based devices--ranging from the now quaint vacuum tube to today's 
million-transistor microchips. Those conventional electronic devices move 
electric charges around, ignoring the spin that tags along for the ride on 
each electron. 　

(to be continued)