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New Memristor Makes Low-Cost, High-Density Memory
KentuckyFC writes "A group of electronics engineers have discovered that a thin layer of vanadium oxide acts as a memristor, the fourth basic component of circuits after resistors, capacitors, and inductors that was discovered last year. At a critical temperature, a current passing through the layer causes it to change from an insulating state to a metal-like state, thereby changing its resistance (abstract). The effect lasts many hours — which is what makes the layer a memristor (a resistor with memory). The team says this could be scaled up to make resistive random access memory, or RRAM, at very low cost, from little more than layers of vanadium oxide."
The article suggests use as resistive RAM rather than a solid state drive. As long as it doesn't need to be a permanent memory element it might be possible to refresh periodically on a schedule that's safely less than the lifetime of the state transition, i.e. boost the phenomenon every hour or two. Shouldn't cause much of a power hit.
I thought the more exciting announcement was that memristors could be tripled up to create transistors that were (despite being tripled up) still much smaller than a standard transistor.
Then, there were bits about them supporting more than just binary states, which would increase complexity and density yet again.
Denser memory may be the first pratical consumer product, but if the other possiblities work out, I'm pretty sure that memory will also be the least significant.
The memristor is is just a way to model nonlinear circuit elements and is one of many components in a nonlinear expansion for circuit modeling. See this paper by Leon Chua, the memristor's inventor. Note that in this paper the fourth element of the four element torus is negative resistance and not the memristor. All of the publicity over the memristor has been (sucessfull) marketing by some researchers at HP. .
From the talk page for the memristor on wikipedia
"Resistance, Capacitance and Inductance are regarded as fundamental because to each there corresponds a different picture of what is going on with the energy. Resistance refers to the loss of energy to Joule heating. Capacitance refers to storage of energy in the electric field. Inductance refers to storage of energy in the magnetic field.
If memristance is the "fourth fundamental" circuit element then memristors must do something with the energy they are imparted other than turn it into heat, or store it in electric or magnetic fields. So what do memristor supporters have to say about this? nothing. This is not surprising, since the concept of memristance stems from a purely mathematical argument bent on taming the current/voltage relationships of nonlinear circuit elements. The concept of memristance was invented out of convenience to avoid dealing with frequency-dependent (time-dependent) resistance, inductance, and capacitance. Thus the memeristor is not "fundamental", unless in your book fundamental is synonymous with convenient."