One thing that's kept engineers from copying the brain's power efficiency and quirky computational skill is the lack of an electronic device that can, all on its own, act like a neuron. It would take a special kind of device to do that, one whose behavior is more complex than any yet created.
Suhas Kumar of Hewlett Packard Laboratories, R. Stanley Williams now at Texas A&M, and the late Stanford student Ziwen Wang have invented a device that meets those requirements. On its own, using a simple DC voltage as the input, the device outputs not just simple spikes, as some other devices can manage, but the whole array of neural activity—bursts of spikes, self-sustained oscillations, and other stuff that goes on in your brain. They described the device last week in Nature.
It combines resistance, capacitance, and what's called a Mott memristor all in the same device. Memristors are devices that hold a memory, in the form of resistance, of the current that has flowed through them. Mott memristors have an added ability in that they can also reflect a temperature-driven change in resistance. Materials in a Mott transition go between insulating and conducting according to their temperature. It's a property seen since the 1960s, but only recently explored in nanoscale devices.
From IEEE Spectrum
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