Here is an important detail, many seem to have overlooked :
["The UCL devices also display a continuously variable resistance that depends on the last voltage that was applied."]
Current Flash already allows Multi-Bit cells, so any alternative is going to have to have the same ability, in order to be far enough ahead of flash, to be worth the bother.
My lasting impression of MLC is someone showing a distribution with tail bits and saying "this shows MLC capability"..ok.
If the resistance depends on the last voltage applied, that may not be so useful for memory, but maybe for a memristor.
ReRAM is the most awaited replacement of Flash RAM if it get successful implementation as compared to FlashRAM. It really need Chemical Engineers and Nano Technology experts working behind the early invention of the possibilities associated with ReRAM.
I think the key to a successful product introduction is the controller in front of the bucket-o-bits. As long as the controller interface is such that the CPU is indifferent to what's behind it then they can quickly get competitive products out into the market in standard storage formats. That'll free them up to sell the advantages of this technology over NAND - faster, lower-power, lower costs etc.
Interesting claims they have on being first. Others besides James Tour have published recently on SiOx RRAM--Jack Lee of UT-Austin, and Hyunsang Hwang of Gwangju University, Korea with Luigi Pantisano of IMEC. There are also a few published reports from the '70's, one by MJ Howes and another by RM Anderson.
Two more examples, which were previously cited by Blaise Mouttet, infamous Memristor denier:
D. R. Lamb and P. C. Rundle, "A non-filamentary switching action in thermally grown silicon dioxide films", Br. J. Appl. Phys. 18, 29-32 (1967)
Dow Corning also did work on SiO2 ReRAM in the early 1990's (US Patent 5283545).
I prefer memristor realist rather than "memristor denier." I initially supported HP's work on memristors until I figured out that it was mostly propaganda to support their business agenda rather than legitimate science.
But why is it important how they call their device...
Isn't only important thing what device can do?
If HP produce device to match flash or to do something useful - call it memristor, or ReRAM or whatever it is irrelevant.
The "memristor" represents a mathematical model formulated by Leon Chua in the 1970's. If the memristor model is a wrong mathematical model for ReRAM then its acceptance will probably hinder scientific development.
If the figures of merit are speed, size, energy and so on, calling something memristor or not wouldn't affect it.
Nobody really ended up with any real disadvantage for calling ReRAM 'a memristor' as nobody is using Chua's model to improve any important parameters anyway..
People are using name memristor (instead ReRAM) as it is more catchy but nobody really backs up anything on Chua's model.
I simply can't see any real problem with that.
If I got it right this is the bulk effect and Rice's study is more related to SiO2 substrates where the formation is on the surface - one of the reasons it doesn't work in the air.
NDR effect is known for many years but the operational device with properties to match flash and be cheap is different thing...
In the overall cost of a RRAM chip, deposition of a few hundred angstroms of most metal oxides (eg. TiO2, Al2O3, HfO2, NiO, etc) is not significantly more expensive than deposition of silicon oxide, so it's not likely a cost driver.
On their website they stated 3k, Tour's group
10k, and Hwang's group 100k.
So silicon dioxide is more or less similar to other metallic oxides in these terms.
HP will come there first anyway - but it is interesting to see if silicon can fight back once again.
Very nice article in IEEE Spectrum about SiOx RRAM.