LONDON – Blaise Mouttet, of Arlington, Virginia, has published a theoretical paper on arXiv.org (see http://arxiv.org/abs/1201.2626
entitled "Memresistors and non-memristive zero-crossing hysteresis curves" that seeks to demonstrate that there are multiple dynamic systems which fall outside the constraints of the so-called memristor, two-terminal memory device and yet produce zero-crossing hysteresis curves.
The paper begins with the sentence "It has been erroneously asserted by the circuit theorist Leon Chua that all zero-crossing pinched hysteresis curves define memristors."
Blaise Mouttet argues that the interpretation of the memristor as a fourth fundamental circuit element – after the resistor, capacitor and inductor – was incorrect and that the memory device under development at HP Labs is not actually a memristor but part of a broader class of variable resistance systems.
Memristor theory was formulated and named by Professor Leon Chua in "Memristor - The missing circuit element" IEEE Trans. Circuit Theory CT-18, 507-519 (1971), which sought to define a fundamental non-linear circuit element whose existence and behavior was covered by electromagnetic theory. Hewlett-Packard Co. (HP) adopted the use of the memristor term for a metal-oxide resistive RAM technology it began to develop some time before 2008.
Mouttet presented a paper at the 2010 International Symposium on Circuits and Systems (ISCAS) that also argued that the HP Labs memory element is not a memristor and claimed that Samsung, not HP, owns the basic U.S. patent on titanium oxide resistance memory (U.S. Patent 7,417,271).
Since publishing his arXiv paper Mouttet has also been in discussion with an e-mailing list of researchers into non-volatile memory device physics.
Some e-mail correspondents have come out in favor of Mouttet's position stating that trying to define any two-terminal device in which the resistance can be altered by the current passed through the device as a memristor, adds nothing to the understanding of a complex field in which there are many types of device.
These different devices include: Resistive RAM (RRAM or ReRAM), phase-change memory (PCM) or phase-change RAM (PCRAM), conductive-bridging RAM (CBRAM), ferroelectric RAM (FRAM) as well as ferroelectric polarization memories made using organic materials.
Mouttet also publishes a nanotechnology web-log under the name TinyTechIP at http://tinytechip.blogspot.com/Related links and articles:
Memresistors and non-memristive zero-crossing hysteresis curves
HP, Hynix plan to launch memristor memory in 2013
IMEC claims ReRAM filament breakthrough
Samsung reports trillion-cycle ReRAM
HP discovers memristor mechanism