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Comment by heydenberk | Hacker News Reader

Are memristors real? This paper[0] in addition to a handful that have appeared on HN in the last few months asserts that "the 2008 memristor is not the 1971 postulate and neither of them is fundamental" and moreover that "[t]he ideal memristor is an unphysical active device and any physically realizable memristor is a nonlinear composition of resistors with active hysteresis."

I'm confused by something like this being an open question, and even more confused about why this debate isn't lighting up the electrical/computer engineering community as far as I can tell.

[0] https://www.nature.com/articles/s41598-018-29394-7

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I asked this question several years ago[0], and had some very interesting responses. The long and short of it was that yes, they are real, and you can make them yourself. The basic concept being that different metal oxides have different resistances; so if you make a "sandwich" like metal_1-oxide-metal_2 you can use current to move the oxygen ions from one metal to the other. The resistance of the sandwich changes as you do so, and stays set in between applications of charge, as well as staying set if the probing current is not too high. I recall making one was a fun afternoon project.

[0]https://electronics.stackexchange.com/questions/76097/what-a...

[1]http://sparkbangbuzz.com/memristor/memristor.htm

If you don't like the PR, just call it ReRAM. Few people actually care about HP's grandiose claims, a lot of people care about the actual performance of the devices.

It’s also worth pointing out that all ideal circuit devices are non physical.

But yes I think the name “memristor” is mostly PR.

> It’s also worth pointing out that all ideal circuit devices are non physical

This is not a useful statement - in this framing, all of circuit theory is unphysical.

Other ideal circuit elements could exist in the sense that their existence would not violate known physical laws. The criticisms of the memristor is that its existence would violate fundamental thermodynamic principles (esp. Landauer's principle).

I mean, an ideal voltage source also cannot exist, and I'm sure their existence would violate several laws of physics. For example what happens when you put two ideal voltage sources in parallel? or when you connect one to a short circuit?

Despite that though we can use a combination of ideal elements to represent real, non ideal, physical devices. So in that sense I disagree with your statement that "in this framing, all of circuit theory is unphysical."

I don't have a clue in general, but I thought hysteresis was memory by definition.

It's 95% marketing and 5% engineering. There's not much to get excited about. (yet?)

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