4 ms·

Memristors built with 2-nanometer-thick parts

81 points by ToFab123 8y ago

heydenberk 8y ago
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 https://www.nature.com/articles/s41598-018-29394-7
- bronson 8y ago
  It's 95% marketing and 5% engineering. There's not much to get excited about. (yet?)
- Tuna-Fish 8y ago
  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.
- sgillen 8y ago
  It’s also worth pointing out that all ideal circuit devices are non physical. But yes I think the name “memristor” is mostly PR.
  - twtw 8y ago
    > 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).
    - sgillen 8y ago
      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."
- perl4ever 8y ago
  I don't have a clue in general, but I thought hysteresis was memory by definition.
- aperrien 8y ago
  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-are-the-characteristics-of-a-memristor https://electronics.stackexchange.com/questions/76097/what-a... [1]http://sparkbangbuzz.com/memristor/memristor.htm http://sparkbangbuzz.com/memristor/memristor.htm
peter_d_sherman 8y ago
I can just picture William Devane telling everyone to buy Platinum now...<g>
aaaaaaaaaab 8y ago
Can’t wait to have some of these memristors in my phone, powered by graphene batteries, running on clean electricity from the regional fusion plant.
- csours 8y ago
  The future sounds beautiful.
  - PuffinBlue 8y ago
    And only about 30 years away for as long as I can remember.
- TimTheTinker 8y ago
  > regional fusion plant You mean the sun, right?
  - B1FF_PSUVM 8y ago
    People don't realize that solar is not a "fair trade" energy, that celestial body is being ruined to supply our egotistical needs ...
- fiblye 8y ago
  And the year after that will be the year of the Linux desktop.
  - jacobush 8y ago
    ... yes because that will be after the apocalypse and what remained of working pre-war technology were ancient "desktop computers". Big hulking things you couldn't put in your pocket, much less implant and connect to your brain. But they worked, and some source code was available. It was called "Linux".
  - goodcanadian 8y ago
    I understand the joke, but I've been running Linux on my desktop for something like 15 years. ;-)
deepnotderp 8y ago
To address the memristor existence questions: if you define a memristor as a device which "remembers" its resistance via a pinched hysteresis I-V curve, then we have had ReRAM/ memristor devices for some time now. On the other hand, if you define memristor as a device with coupling between charge and flux, then no. Practically speaking, it's unlikely that memristors will replace transistors because they're about 500X too slow and have about a billion times less endurance. Same issue with memory replacement. They could in theory make excellent flash memory replacement, but currently sneak paths, thermal crosstalk and ion crosstalk remain challenges
rini17 8y ago
So, 11 atoms thick layer of platinum is major cost consideration? No, just bad journalism.

81 points by ToFab123 8y ago

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

bronson 8y ago
It's 95% marketing and 5% engineering. There's not much to get excited about. (yet?)
Tuna-Fish 8y ago
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.
sgillen 8y ago
It’s also worth pointing out that all ideal circuit devices are non physical. But yes I think the name “memristor” is mostly PR.
- twtw 8y ago
  > 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).
  - sgillen 8y ago
    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."
perl4ever 8y ago
I don't have a clue in general, but I thought hysteresis was memory by definition.
aperrien 8y ago
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-are-the-characteristics-of-a-memristor https://electronics.stackexchange.com/questions/76097/what-a... [1]http://sparkbangbuzz.com/memristor/memristor.htm http://sparkbangbuzz.com/memristor/memristor.htm

peter_d_sherman 8y ago

I can just picture William Devane telling everyone to buy Platinum now...<g>

aaaaaaaaaab 8y ago

Can’t wait to have some of these memristors in my phone, powered by graphene batteries, running on clean electricity from the regional fusion plant.

csours 8y ago
The future sounds beautiful.
- PuffinBlue 8y ago
  And only about 30 years away for as long as I can remember.
TimTheTinker 8y ago
> regional fusion plant You mean the sun, right?
- B1FF_PSUVM 8y ago
  People don't realize that solar is not a "fair trade" energy, that celestial body is being ruined to supply our egotistical needs ...
fiblye 8y ago
And the year after that will be the year of the Linux desktop.
- jacobush 8y ago
  ... yes because that will be after the apocalypse and what remained of working pre-war technology were ancient "desktop computers". Big hulking things you couldn't put in your pocket, much less implant and connect to your brain. But they worked, and some source code was available. It was called "Linux".
- goodcanadian 8y ago
  I understand the joke, but I've been running Linux on my desktop for something like 15 years. ;-)

deepnotderp 8y ago

To address the memristor existence questions: if you define a memristor as a device which "remembers" its resistance via a pinched hysteresis I-V curve, then we have had ReRAM/ memristor devices for some time now. On the other hand, if you define memristor as a device with coupling between charge and flux, then no. Practically speaking, it's unlikely that memristors will replace transistors because they're about 500X too slow and have about a billion times less endurance. Same issue with memory replacement. They could in theory make excellent flash memory replacement, but currently sneak paths, thermal crosstalk and ion crosstalk remain challenges

rini17 8y ago

So, 11 atoms thick layer of platinum is major cost consideration? No, just bad journalism.