Saturday, September 5, 2009

Logic That Feels the Noise

As microchips shrink, the inescapable electronic buzz that emerges from thermal fluctuations, cross talk between wires and other sources can endanger their proper function. A way around that problem could be stochastic resonance, a phenomenon in which noise can boost a weak signal and improve a system’s performance. Certain kinds of structures, such as a sensory nerve, will output a signal only when background noise is sufficiently high. Researchers at Arizona State University constructed logic gates—circuit elements that perform logic functions— that behave in a similar way. When noise levels are low, the gates perform unreliably; however, at the kinds of noise levels expected for the smallest transistors, they work correctly. Such unusual, nonlinear behavior could help microchips get smaller. Moreover, altering certain applied voltages in the circuit can reconfigure the gate on the fly, thereby creating a morphing processor. Tune in to the March 13 issue of Physical Review Letters for more details. —Charles Q. Choi

Source of Information : Scientific American(2009-05)

No comments: