Let our colleagues decide if memristors belong to our area of interest.
Today (May 1) it is an epidemic of hits re. this subject- 2600 this morning
9600 now (local time 19.30) It seems an important new element of circuits. My instinct says there will be many applications.
Does the memristor belong to nanotechnology? What do you think?

Views: 58

Reply to This

Replies to This Discussion

Maintaining Moore's law with new memristor circuits

By Ethan Gutmann | Published: May 01, 2008 - 09:55AM CT

In the past, electronic circuit theory has revolved around three fundamental components: the resistor, the capacitor, and the inductor. Now a fourth has been added to that list, the memristor. First postulated in 1971 by Leon Chua at the University of California at Berkeley, a working example was recently created by Dmitri Strukov and colleagues at HP Labs. This advance could help shrink transistors even further.

Chua suspected that a memristor should exist based primarily on symmetry. There are four fundamental circuit variables: electric current, voltage, charge, and magnetic flux. For these variables, we have resistors to relate current to voltage, capacitors to relate voltage to charge, and inductors to relate current to magnetic flux, but we were missing one to relate charge to magnetic flux. That is where the memristor comes in.

The memristor relates magnetic flux to charge, but once you dive into the math, it actually boils down to a variable resistance as a function of the charge passed through it. As the authors state, "The fact that the magnetic field does not play an explicit role in the mechanism of memristance is one possible reason why the phenomenon has been hidden for so long; those interested in memristive devices were searching in the wrong places."

The group at HP Labs discovered the memristor by looking at a known phenomenon. They knew that the resistance of titanium dioxide changed with exposure to oxygen, a fact that has been used to create oxygen sensors. The memristor created in HP labs is based on a film of titanium dioxide, part of which is doped to be missing some oxygen atoms. It is these crystal defects that allow an electric current to pass through titanium dioxide, thus the more holes, the lower the resistance.

These holes can be driven from one side to the other by passing a charge across the film. This decreases the average resistance of the entire film. By passing a charge in the opposite direction, the holes can be pushed back. This process can be repeated, effectively turning the memristor off and on, or making it a one or a zero. Of course, you might expect that measuring this resistance by applying voltage should change the resistance. The authors avoid this by using an alternating current; as the current is moving back and forth, there is no net change in resistance.

Currently the good folk at HP Labs have exploited this to create simple data storage devices. Using memristors, they have been able to store 100 gigabits on a single die in one square centimeter. That is substantially more than the 16 gigabits for a single flash chip, and a comparable storage density to modern hard drives. In the future, HP thinks they can get that up to a terabit or more per centimeter... with the access speed of DRAM. Clearly, this will vie with other technologies such as IBM's racetrack memory. Of course, storage is only one possible role for memristors.

Memristors could also be useful in creating analog processors. When there is a smaller change in charge, the change in resistance is also smaller. The authors suggest that this could lead to the development of transistors akin to neurons, in which increased use leads to increased conductance.

A final beauty of memristors comes from their response to decreasing size. The smaller the device, the more important memristance becomes. Conventional electronic circuits have ever increasing problems with heat and leakage at smaller sizes, but memristance is proportional to the inverse of the square of the film thickness, so smaller films mean a stronger memristance effect. By developing transistors based on memristors, we may be able to
one article about memristors in hungarian:


Reply to Discussion


Welcome - about us

Welcome! Nanopaprika was cooked up by Hungarian chemistry PhD student in 2007. The main idea was to create something more personal than the other nano networks already on the Internet. Community is open to everyone from post-doctorial researchers and professors to students everywhere.

There is only one important assumption: you have to be interested in nano!

Nanopaprika is always looking for new partners, if you have any idea, contact me at editor@nanopaprika.eu

Dr. András Paszternák, founder of Nanopaprika

Publications by A. Paszternák:

Smartphone-Based Extension of the Curcumin/Cellophane pH Sensing Method

Pd/Ni Synergestic Activity for Hydrogen Oxidation Reaction in Alkaline Conditions

The potential use of cellophane test strips for the quick determination of food colours

pH and CO2 Sensing by Curcumin-Coloured Cellophane Test Strip

Polymeric Honeycombs Decorated by Nickel Nanoparticles

Directed Deposition of Nickel Nanoparticles Using Self-Assembled Organic Template,

Organometallic deposition of ultrasmooth nanoscale Ni film,

Zigzag-shaped nickel nanowires via organometallic template-free route

Surface analytical characterization of passive iron surface modified by alkyl-phosphonic acid layers

Atomic Force Microscopy Studies of Alkyl-Phosphonate SAMs on Mica

Amorphous iron formation due to low energy heavy ion implantation in evaporated 57Fe thin films

Surface modification of passive iron by alkylphosphonic acid layers

Formation and structure of alkylphosphonic acid layers on passive iron

Structure of the nonionic surfactant triethoxy monooctylether C8E3 adsorbed at the free water surface, as seen from surface tension measurements and Monte Carlo simulations

Next partner events of TINC

We are Media Partner of: