What are “actual pictures” of atoms actually pictures of? • Hacker News Board

Re: What are “actual pictures” of atoms actually pictures of?

#11

Post by kens » Sat, Jun 25, 2016, 8:21 PM UTC

lisper wrote: post #7

One of my first jobs out of college was doing manual chip layouts (which will give you some idea of how old I am). Once the layout was done, the design was sent to a "mask house" which would print the layout onto a series of glass plates (the "masks") which were then used in the chip fabrication process. When the masks for my first chip came back I popped one of them into a bench microscope to see what it looked like…

What era of chip layout was this? I'm surprised that manual chip layout was still being done when chip features were that small. I look at 1970s chips a lot, and the features are easily visible under a microscope, as they are much larger than wavelength-sized.

Re: What are “actual pictures” of atoms actually pictures of?

#12

Post by Stratoscope » Sat, Jun 25, 2016, 8:30 PM UTC

semi-extrinsic wrote: post #2

Well, as the article points out, the things being imaged are most definitely actual atoms. The only thing TFA is nitpicking about is that light isn't used to image those atoms. This is about as interesting as pointing out the fact that an ultrasound picture of a baby isn't an "actual picture", since we use sound instead of light to make the image.

I found the article really interesting and learned a few things from it.

I do know how an ultrasound image works, and I had some basic knowledge about scanning tunneling microscopes, but this article - and the many links in it - were definitely worth my time reading.

Re: What are “actual pictures” of atoms actually pictures of?

#13

Post by Stratoscope » Sat, Jun 25, 2016, 8:32 PM UTC

fluxsauce wrote: post #8

> This technology has been around for decades and, like the advent of the synth, has given rise to all manner of jackassery. What's with the synthesizer hate? That seems random.

That was the weirdest part of this article. I enjoyed the whole thing until the end, but why does the author call IBM's cute and amazing movie "A Boy and His Atom" jackassery?

Re: What are “actual pictures” of atoms actually pictures of?

#14

Post by joncrocks » Sat, Jun 25, 2016, 8:43 PM UTC

semi-extrinsic wrote: post #9

Animats wrote: post #5

Earlier quoted context omitted.

The concept of the scanning tunneling microscope is so simple and ridiculous that it was probably thought of and dismissed long before someone built one. "You're going to image atoms by dragging a tiny needle across them"? Yet that's pretty much how it works. The first one was built in 1981, but one could have been built in the 1950s. Piezoelectric crystals were known. Raster scanning circuits were known. Feedback ci…

I know, I did a benchtop STM lab for my Nuclear Physics course some years ago. Most of the day was spent trying to make single atom needles by a wrist-flick technique for cutting platinum wire with some sharp pliers.

I worked in the lab at the Nation Physical Lab in the UK that had the low pressure + low temperature STM, we used to make the tips by dipping the ends in a very strong solution of NaOH. You relied on the surface tension as it dissolved to produce you a very sharp tip.

Surprisingly easy.

Re: What are “actual pictures” of atoms actually pictures of?

#15

Post by pizza » Sat, Jun 25, 2016, 8:53 PM UTC

semi-extrinsic wrote: post #9

Animats wrote: post #5

Earlier quoted context omitted.

The concept of the scanning tunneling microscope is so simple and ridiculous that it was probably thought of and dismissed long before someone built one. "You're going to image atoms by dragging a tiny needle across them"? Yet that's pretty much how it works. The first one was built in 1981, but one could have been built in the 1950s. Piezoelectric crystals were known. Raster scanning circuits were known. Feedback ci…

I know, I did a benchtop STM lab for my Nuclear Physics course some years ago. Most of the day was spent trying to make single atom needles by a wrist-flick technique for cutting platinum wire with some sharp pliers.

Could you post a quick summary describing the technique? Sounds like my definition of esoteric fun, haha.

Re: What are “actual pictures” of atoms actually pictures of?

#16

Post by lisper » Sat, Jun 25, 2016, 8:56 PM UTC

kens wrote: post #11

lisper wrote: post #7

One of my first jobs out of college was doing manual chip layouts (which will give you some idea of how old I am). Once the layout was done, the design was sent to a "mask house" which would print the layout onto a series of glass plates (the "masks") which were then used in the chip fabrication process. When the masks for my first chip came back I popped one of them into a bench microscope to see what it looked like…

What era of chip layout was this? I'm surprised that manual chip layout was still being done when chip features were that small. I look at 1970s chips a lot, and the features are easily visible under a microscope, as they are much larger than wavelength-sized.

This was in 1984, and it was for experimental chips, not production chips. The layout was done using CAD tools, but the placement was all manual.

Also, I think they were analog chips, not digital. I'm not sure. This was a co-op job in my first year at college at the IBM plant on Cottle Road, and I was never fully in touch with the big picture. I think they were making big-ass hard drives, and the chips I was working on were part of the circuitry that amplified the raw signal from the read-write head, but those details were way above my pay grade.

Re: What are “actual pictures” of atoms actually pictures of?

#17

Post by blowski » Sat, Jun 25, 2016, 8:59 PM UTC

Artlav wrote: post #4

Well, an image is a representation of something in a way that humans can see. Whether waves, electrons or poking sticks were used doesn't change the fact of it being an image. Say, a dolphin's echolocation might let him "see" a diver using sound - http://i.imgur.com/CS6wkNV.png , which would still be considered an image, even though it's using sound. Anyway that's just semantics, and an STM is still a damn impressive…

Yeah, it's not a photo but it is an image or picture. The article is doing a bad job of defining its terms, but still it's interesting for a layman like myself.

Re: What are “actual pictures” of atoms actually pictures of?

#18

Post by jdetle » Sat, Jun 25, 2016, 9:12 PM UTC

I strongly encourage anyone who is thinking about this to read: "A Different Universe" by Robert Laughlin. This is one of his main concerns of modern science, and although its kind of a muddled argument he thinks that the emergent phenomena captured by photographs are entirely misapplied to atomic forces.

Re: What are “actual pictures” of atoms actually pictures of?

#19

Post by foota » Sat, Jun 25, 2016, 9:18 PM UTC

Stratoscope wrote: post #13

fluxsauce wrote: post #8

> This technology has been around for decades and, like the advent of the synth, has given rise to all manner of jackassery. What's with the synthesizer hate? That seems random.

That was the weirdest part of this article. I enjoyed the whole thing until the end, but why does the author call IBM's cute and amazing movie "A Boy and His Atom" jackassery ?

I think it's being used to mean a sort of playing around.

Re: What are “actual pictures” of atoms actually pictures of?

#20

Post by lanna » Sat, Jun 25, 2016, 9:20 PM UTC

semi-extrinsic wrote: post #2

Well, as the article points out, the things being imaged are most definitely actual atoms. The only thing TFA is nitpicking about is that light isn't used to image those atoms. This is about as interesting as pointing out the fact that an ultrasound picture of a baby isn't an "actual picture", since we use sound instead of light to make the image.

It is the distinction between pictures and photographs: they definitively are pictures of atoms, but they aren't nor could ever be photographs.

Ultrasounds also are pictures, but not photographs.