
Homemade Memristor (2011) - ksrm
http://sparkbangbuzz.com/memristor/memristor.htm
======
alexbock
Another source on what appears to be the same sulfur compound with some more
curves: [http://www.eevblog.com/forum/projects/making-a-
memristor/](http://www.eevblog.com/forum/projects/making-a-memristor/)

Is anyone aware of a good simulator for one of these curve tracers? I
understand the idea of a memristor, but it's not immediately intuitive to me
why it should make this particular shape (and I'm unsure which "arm" of the
eight is taken when the voltage is going up and when it is going down -- I
assume the bottom is traveled upwards and the top is traveled downwards). It
would be nice to see one animated or with a third time dimension. (The figure
eight is more apparent in the link I mentioned above, although you can see it
in this submission once you know what you're looking for.)

~~~
smalley
The family of these materials are often referred to as chalcogenides (although
strictly speaking they don't always include only metals from that periodic
group). They've been investigated quite a bit for use in phase change memory
if you have access to academic journals (I could probably root around later
and see what's not behind a paywall).

The strange looking curve is really kind of two parts forward biasing/reverse
biasing. Assuming you're starting from a virgin device you move along the
curve where you're sweeping the voltage upwards but not really getting much
increase in current (since there's no real channel yet). In these materials
the mechanism is the establishment of little "fingers" of metal migrating and
completing the circuit. As the "fingers" move forward you suddenly start
seeing more and more current without increasing voltage (your effective
resistance is dropping) and then jumps up as the connection is made.
Eventually you sweep the voltage backwards. Something similar happens in the
part of the AC curve in reverse.

There is a really good diagram in this paper: "Mechanism for resistive
switching in chalcogenide-based electrochemical metallization memory cells"
from Zhuge et al
[http://scitation.aip.org/content/aip/journal/adva/5/5/10.106...](http://scitation.aip.org/content/aip/journal/adva/5/5/10.1063/1.4921089)

------
Stratoscope
I love it! "I found some smelly corroded metal objects, so I must investigate
their electrical properties."

Serendipitous science at its best! Or, how to increase your luck surface area.

~~~
alexbock
Cat's whisker diodes and the initial discovery of the LED are other good
examples of this. Connect a small wire to the right kind of rock (or rusty old
razor blade) just right and you get a diode. If you get it just perfect (and
use the right kind of rock) you'll even get a faint LED.

~~~
GregBuchholz
For those who want to experiment with their own LEDs, they should check out:

[https://web.archive.org/web/20120913060200/http://neazoi.com...](https://web.archive.org/web/20120913060200/http://neazoi.com/homemadeled/index.htm)

~~~
simcop2387
This is also a neat place to start with making your own OLEDs.
[https://www.youtube.com/watch?v=CAgRF8TibJ0](https://www.youtube.com/watch?v=CAgRF8TibJ0)

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GregBuchholz
Be sure to check out the rest of this guys stuff, like the homemade CRT, flame
triode, magnetic amplifiers, etc.

[http://www.sparkbangbuzz.com/](http://www.sparkbangbuzz.com/)

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bitwize
Ah, 90s web design, replete with a link urging the reader to "Join the Blue
Ribbon Online Free Speech Campaign!"

I miss the old web.

~~~
userbinator
The page is under 5KB and loads quickly, it's content-full and isn't over-
designed. A quick look at the source shows that it's hand-written. Very nice
indeed.

Funny that browsers now need to have a special "reader mode" specifically to
make pages look like this.

~~~
agumonkey
Completing the circle isn't it. The web 2.0 experiment concludes that old mail
and html3 were actually fine for actually useful browsing.

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kens
The IBM 1401 restoration team found some corroded germanium transistors that
seemed to show memristor-like behavior:
[http://ibm-1401.info/GermaniumAlloy.html#CommentsGarner](http://ibm-1401.info/GermaniumAlloy.html#CommentsGarner)
(scroll to the p.s.) If anyone can explain this behavior, they would be
grateful.

To change topic, progress on memristors seems painfully slow. In comparison,
it took just 10 years from the invention of the transistor until IBM's
president forced the company to give up tubes and switch to transistors. And
it was just 4 years from the invention of the first IC until NASA decided to
use them in the Apollo Guidance Computer and landed them on the moon a few
years later.

~~~
IanCal
> To change topic, progress on memristors seems painfully slow.

I think that's a little unfair. They were first shown just 7 years ago, and
have already been used to build (extremely) simple neural networks.

Transistors took ~6 years before they were sold in commercial products, and
you can already buy a memristor on a chip.

When transistors were invented, ENIAC was around and had ~18,000 vacuum tubes,
and was the kind of thing _governments_ built. In 2008 you could wander into a
shop and pick up something like this:
[http://ark.intel.com/products/37147](http://ark.intel.com/products/37147)
which has 730 million transistors.

I think it's understandable that it'll take a bit longer for memristors to
overtake transistor based processors.

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comboy
Associated youtube:
[https://www.youtube.com/watch?v=MlswP_qXbdA](https://www.youtube.com/watch?v=MlswP_qXbdA)

not sure why it's not linked on the website

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ndesaulniers
Neat, he's even got the pinched hysteresis loop going on.

The first talk I ever gave was on Memristors at a Rochester Bar Camp in '09 as
a college freshman:
[https://docs.google.com/presentation/d/1GVqEeFUJyI7VmzqYPabQ...](https://docs.google.com/presentation/d/1GVqEeFUJyI7VmzqYPabQ9DOC32rdQv-
YN3YCzO6vvlY/pub?start=false&loop=false&delayms=3000#slide=id.p4)

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agumonkey
Do memristor have MTBF ?

~~~
kylerpalmer
Yes. Since the mechanism for memristors is either phase-change or filament
production (by ion conduction), they eventually fail, basically just becoming
a normal resistor. The number of cycles of some experimental devices is very
high, though I don't know if anyone has done a true MTBF study on one.

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thinkingkong
Mirror: [http://obtainable-animal.surge.sh/memristor.htm](http://obtainable-
animal.surge.sh/memristor.htm)

