Researchers at Hewlett-Packard’s Information and Quantum Systems Lab have created the memristor, the last to be created of the four fundamental circuit elements, joining resistors, capacitors, and inductors. It’s big news in the Electrical Engineering community as it completes the set and, with development and refinement, should lead to significant new capabilities in the field of electronics, not the least of which is a reduction in the leakage current which plagues modern computer chips.
Leakage current in chips is akin to the problem of a leaky aqueduct: more leakage means inefficiency in water transport – and a lot of soggy ground around the leaks. Leakage current is why chips get hot when they run; in personal computers, modern CPUs leak so much electricity that they need at a minimum fan-assisted heatsinks to keep from self-destructing when under load, and motherboards now use cross-connected heatpipes and heatsinks on support chips to keep them from burning themselves out. It’s a problem that’s gotten bad and is getting worse; the main driver of increased chip speed for the last two decades has been feature shrink – smaller circuitry – which in turn has the natural side effect of making the circuitry faster, but feature shrink also results in an increase in leakage current. The writing on the walls has been clear for years: if this problem is not mitigated it will be the limiting factor to what has been the most effective means of making computers faster and cheaper.
Memristors may or may not be a big part of the solution to the leakage current problem in semiconductors, but this discovery is not just adding another class of widget to the toolbox of electrical engineers: it’s going to rewrite their textbooks on electronics. As this article in EETimes explains:
The hold-up over the last 37 years, according to professor Chua, has been a misconception that has pervaded electronic circuit theory. That misconception is that the fundamental relationship in passive circuitry is between voltage and charge. What the researchers contend is that the fundamental relationship is actually between changes-in-voltage, or flux, and charge. Such is the insight that enabled HP to invent the memristor, according to Chua and Williams.
What astonishes me is that such changes are possible even today. Just as the discoveries of dark energy and dark matter have turned upside-down our understanding of the composition of the universe, so too are there discoveries being made which render our understanding of basic principals in well-studied fields moot. How did we get so far while still not knowing this? The tragedy of scientific understanding that it is usually wrong, but it is only through self-correction that we know that to be so, and in that self-correction we see the strength of science.