This blog is a slight variation from the typical nanotechnology ones. The frequency of the mention of memristors has been increasing. Memristors are novel components of circuits which improves in performance as their size moves into the nano realm.. I have been fortunate to be in attendance for a Stan Williams, HP VP and Senior Fellow, presentation at UCLA in December 2007, where he presented the concept of the memristors. There is a posting of a more recent talk that he has given on the memristor.  The fact that it has taken seven years to start being brought into the popular press is not surprising.
The first question is: What is a memristor? Electrical circuits contain passive elements of resistors, capacitors, and inductors. A memristor is a fourth classification of an electrical circuit that maintains a time relationship between current and voltage between two terminals.  Leon Chua  proposed the concept of the memristor in 1971 as a component that related electric charge and magnetic flux. It took until 2008 for HP researchers to find the memristor based on an analysis of a thin film of titanium dioxide. The memristor electrical resistance is not constant but a history of the current, including direction, that has flowed through the device. A key attribute of the device is that when the poser is turned off, the memristor “remembers” its existing state. Miniaturization into the nano realm actually is beneficial for memristors in that the functionality becomes stronger as their feature size shrinks.
The next question is: So What? There are many possibilities. Since the device has a memory when power is turned off, it acts like non-volatile RAM. The device retains the state information unlike binary “on” and “off” states. The potential exists to create devices that have a number of stored states. This will result in less power consumption to maintain more data than current approaches. At a Las Vegas conference in June 2014, HP announced a plan to develop a system by the end of the decade. They are projecting to have memristor based DIMMs that combine the high storage densities of hard disks and the high performance of DRAM.  It will be interesting to watch the development of memristors and the resulting applications. Keep watching for memristors as circuitry continues to decrease in size.