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Switching (“Memristor”) effects
Memristors are electronic devices whose resistance exhibits a memory of their previous state. First proposed6 in 1971 as a magical fourth circuit element that is complementary to the resistor, inductor, and capacitor, the proposal was largely forgotten, until two years ago the missing memristor was ‘found’.7 This discovery has excited a huge wave of interest, both for fundamental reasons and because of the possibility that these new elements could allow new architectures for integrated circuits (and extensions to Moore’s Law). It has already been shown that memristors allow logic operations to be performed.8 Attempts to describe mechanisms for memristor operation have so far focused on the movement of charged defects in oxide barriers.9 It is highly unlikely, however, that such mechanisms could explain the memristor-like switching behavior that we have observed in percolating - tunneling devices10,11.
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Novel switching behavior in a device formed from Bi clusters with diameters ~30nm, similar to that of memristors.
References
6. L. Chua, ‘Memristor - the missing circuit element’, IEEE Trans. Circuit Theory 18, 507 (1971).
7. D. Strukov, G. Snider, D. Stewart, and R. Williams, ‘The missing memristor found’, Nature 453, 80 (2008).
8. J. Borghetti, G. Snider, P. Kuekes, J. Yang, D. Stewart and R. Williams, ‘‘Memristive’ switches enable ‘stateful’
logic operations via material implication’, Nature 464, 873 (2010).
9. J. Yang, M. Pickett, X. Li, D. Ohlberg, D. Stewart and R. Williams, ‘Memristive switching mechanism for metal/oxide/metal nanodevices’ Nature Nano 3, 429 (2008).
10. M. Schulze, S. Gourley, S. A. Brown, A. Dunbar, J. Partridge, R. J. Blaikie, ‘Electrical Measurements of 11. Nanoscale Bismuth Cluster Films’, Eur. Phys. J. D. 24, 291 (2003).
12. A. Sattar, P. Convers and S. A. Brown, ‘Quantised Conductance in Nanoparticle Switches’, to be published.