5 ms·

>Next, a short but powerful laser pulse is fired into the water jet. This bumps electrons out of the dissolved salts, essentially boosting the conductivity of t

>Next, a short but powerful laser pulse is fired into the water jet. This bumps electrons out of the dissolved salts, essentially boosting the conductivity of the water. A second laser can read back what state the water is in, providing the “on” and “off” options of an existing transistor. Sounds like an optical computer much more than a water computer (compared to e.g. microfluidics), and it's much less surprising that an optical switch would switch fast.

Waterluvian 4y ago
So the water is the copper and the laser is the electrons?
- musingsole 4y ago
  Water is the conductor, yes. Electrons are still the electrons -- excited by or measured by laser
- bee_rider 4y ago
  This is really going to mess up the hydraulic analogy.
  - nullish_signal 4y ago
    It's Water carrying Water, all the way down
  - skykooler 4y ago
    It’s like someone turned https://xkcd.com/2571/ https://xkcd.com/2571/ into reality.
djtango 4y ago
So I've been out of Chemistry for the best part of a decade but I think the novel part of this is exploiting the fact that water based solvents are insanely efficient at propagating charge. Here is some reading I think nay be relevant[0][1][2] but tldr thanks to the miracle of hydrogen bonding, protons/electrons can "transfer" through water by an extremely fast chain reaction of proton association/dissociation - thereby circumventing diffusion as a transfer mechanism. Laser is a useful interface because lasers can be controlled digitally and provide a convenient way of ionising the solution, but this seems like quite a cool hack exploiting the properties of water to me. [0] https://en.m.wikipedia.org/wiki/Grotthuss_mechanism https://en.m.wikipedia.org/wiki/Grotthuss_mechanism [1] https://www.sciencedirect.com/topics/engineering/grotthuss-mechanism https://www.sciencedirect.com/topics/engineering/grotthuss-m... [2] https://pubs.acs.org/doi/10.1021/jz501235y https://pubs.acs.org/doi/10.1021/jz501235y
f1shy 4y ago
The question is: how are the laser an photodiodes driven? Also water? I bet no. Just transistors... so, why not use the transistors switching the laser directly, without the whole laser/water/photodiode path? I do not think this is going anywhere.
- dgoldstein0 4y ago
  I agree it's still time to be skeptical, but it is interesting. Now if they can make a terrahertz adder out of this... then I'll consider getting excited
- ajsnigrutin 4y ago
  > I do not think this is going anywhere. It is... someone published a paper on this, and will get to keep his/her tenure in this horrible publish-or-perish world of academia.
  - samus 4y ago
    Foundational research into principles that leads nowhere is not the problem. The pool of cool ideas like this is unknowably large, and it would be sad to not see papers like this from time time. [Edit: as long as it is a high-quality study of course.] The true problem of the publish-or-perish world is the moral hazard that it causes. In booming fields, it is very seductive to abuse statistics or to outright fake data. These are not always caught by peer review!
- c22 4y ago
  Is there a reason why you couldn't potentially use this same effect to switch the lasers?

Waterluvian 4y ago

So the water is the copper and the laser is the electrons?

musingsole 4y ago
Water is the conductor, yes. Electrons are still the electrons -- excited by or measured by laser
bee_rider 4y ago
This is really going to mess up the hydraulic analogy.
- nullish_signal 4y ago
  It's Water carrying Water, all the way down
- skykooler 4y ago
  It’s like someone turned https://xkcd.com/2571/ https://xkcd.com/2571/ into reality.

djtango 4y ago

So I've been out of Chemistry for the best part of a decade but I think the novel part of this is exploiting the fact that water based solvents are insanely efficient at propagating charge. Here is some reading I think nay be relevant[0][1][2] but tldr thanks to the miracle of hydrogen bonding, protons/electrons can "transfer" through water by an extremely fast chain reaction of proton association/dissociation - thereby circumventing diffusion as a transfer mechanism. Laser is a useful interface because lasers can be controlled digitally and provide a convenient way of ionising the solution, but this seems like quite a cool hack exploiting the properties of water to me. [0] https://en.m.wikipedia.org/wiki/Grotthuss_mechanism https://en.m.wikipedia.org/wiki/Grotthuss_mechanism [1] https://www.sciencedirect.com/topics/engineering/grotthuss-mechanism https://www.sciencedirect.com/topics/engineering/grotthuss-m... [2] https://pubs.acs.org/doi/10.1021/jz501235y https://pubs.acs.org/doi/10.1021/jz501235y

f1shy 4y ago

The question is: how are the laser an photodiodes driven? Also water? I bet no. Just transistors... so, why not use the transistors switching the laser directly, without the whole laser/water/photodiode path? I do not think this is going anywhere.

dgoldstein0 4y ago
I agree it's still time to be skeptical, but it is interesting. Now if they can make a terrahertz adder out of this... then I'll consider getting excited
ajsnigrutin 4y ago
> I do not think this is going anywhere. It is... someone published a paper on this, and will get to keep his/her tenure in this horrible publish-or-perish world of academia.
- samus 4y ago
  Foundational research into principles that leads nowhere is not the problem. The pool of cool ideas like this is unknowably large, and it would be sad to not see papers like this from time time. [Edit: as long as it is a high-quality study of course.] The true problem of the publish-or-perish world is the moral hazard that it causes. In booming fields, it is very seductive to abuse statistics or to outright fake data. These are not always caught by peer review!
c22 4y ago
Is there a reason why you couldn't potentially use this same effect to switch the lasers?