5 ms·
Is single atom thick gold somewhat optically transparent?
by WatchDog 2y ago
Is single atom thick gold somewhat optically transparent?
- Eji1700 2y agoI would suspect it is essentially invisible to the naked eye. It likely only exists in extremely specific conditions, not just like a sheet. I’m guessing it’s somewhat similar to a microscopic layer around a material that we never notice.
- eleitl 2y agoThin gold layers are green, this looks red if you look at the beaker. There are spectral data available in the original publication https://www.nature.com/articles/s44160-024-00518-4 https://www.nature.com/articles/s44160-024-00518-4
- semi-extrinsic 2y agoDefinitely yes. Gold is surprisingly transparent for a metal. Famously, gold plating is used on astronaut helmet visors, at 200 nm thickness - i.e. ~1200 atoms thick.
- twic 2y agoIs it more transparent than other metals? How transparent is a 200 nm film of iron or aluminium?
- Tuna-Fish 2y agoNot transparent at all on visible light wavelengths. Light transmission in metals obeys the skin effect, which means that AC fields (such as the fields in light) do not like to penetrate deep into the material, and the skin depth for visible light wavelengths in most metals is expressed in individual nanometers.
- djtango 2y agoTIL! Thank you for sharing - love me my chemistry after all... For those who are curious: it fends off harmful EM radiation https://spinoff.nasa.gov/spinoff1997/hm2.html#:~:text=A%20thin%20layer%20of%20gold,resistant%20and%20static%2Dfree%20performance https://spinoff.nasa.gov/spinoff1997/hm2.html#:~:text=A%20th....
- manmal 2y agoIt is also used as a coating for window panes, as it‘s great at reflecting infrared radiation (reducing heat loss). My father‘s house has such windows.
- beretguy 2y agoAre those windows expensive?
- spiderfarmer 2y agoYes, but mostly because of the manufacturing process (requires a vacuum).
- formerly_proven 2y agoStealth aircraft also use gold-plated canopies to a) contain emissions from the cockpit to the cockpit b) reflect incoming radiation of a well-defined surface instead of whatever mess is inside the cockpit.
- rrr_oh_man 2y agoI mean, matter is mostly empty space…
- IshKebab 2y agoOnly if you really distort the definitions. The "empty space" you are thinking about is the matter. You can't just put other stuff there. There's a similar wrong meme about how you never really "touch" anything.
- amelius 2y ago> There's a similar wrong meme about how you never really "touch" anything. Ok, what is the exact moment you touch something? How close do the atoms need to be?
- vortegne 2y agoWhen weak interaction starts happening.
- z2h-a6n 2y agoHow about this: two objects are touching when the interaction forces between the objects are of similar magnitude to the interatomic forces within the objects. Very generally speaking, this will happen when the distance between the objects is about the same as the distance between atoms within the objects.