Harnessing the butterfly effect for electronics

"We want to destabilise the whole chip business," says Professor William Ditto. "We are going for the big Home Run here. It's a huge challenge, but we definitely have the technology and the patents organised." It's quite a claim, but Ditto is no maverick – he is currently the chair of the school of Biological and Health Systems Engineering at Arizona State University. And he is convinced that work he and his researchers have done over the last couple of years will transform the semiconductor industry. And the technique he hopes will 'destabilise the chip business'? Ironically, it is chaos. His company, Chaologix, is exploiting the fact that electronic circuits can exhibit 'chaotic' behaviour – deterministic, but fundamentally unpredictable. Normally, you would want to avoid this. But Ditto's team is using chaotic oscillations to build logic gates – or chaogates – and, from them, whole circuits that can switch in nanoseconds from being one device to being another – a processor unit, say, into a graphics controller. A computer built from circuits like these would use its hardware far more efficiently than today's machines and so could be far more powerful. Compared with today's ics, Prof Ditto says chaotic circuits could be up to 100 times faster, easier and cheaper to make, more flexible and robust, and consume less power. It has long been known that electronics devices exhibit chaotic behaviour – like amplifiers producing an oscillating current that can quickly swamp the desired signal. But Prof Ditto realised that, beneath the chaos, the output is cycling through a set of predictable voltages and, by carefully controlling the circuit, it should be possible to stabilise it into any one of a number of states. Out of these states he could build logic gates, and from them circuits. Chaologix is now fabricating prototype chaogates, which today need about 120 transistors – 100 in the control circuit and 20 in the gate circuit. But the number is shrinking all the time, Prof Ditto says, and the latest design uses just two transistors for the chaotic circuit with another 20 in the control circuit. In December 2008, Chaologix received $2million in first round funding and is now hiring staff and looking for more backing to take it to the next level. It is developing two specific applications. One is a 'morphable' element for use in graphics. This will be a reconfigurable portion of a chip, designed to take on the most demanding graphics routines. The other application, which relates to networking, aims to produce chips that can be reconfigured on the fly to provide interfaces to all of the main networking protocols. "We are also exploring a new way of building a search engine chip," Prof Ditto says. "This will use a new chaotic technique, which we have also patented, to speed up searching the web and we have already been contacted by several e-retailers." The technique is a form of parallel search, working in a way somewhat similar to content addressable and associative memories.