4 ms·

This is neither low cost nor commercially relevant. It’s an exotic, low-temperature (so incompatible with subsequent steps of most wafer processes) deposition o

This is neither low cost nor commercially relevant. It’s an exotic, low-temperature (so incompatible with subsequent steps of most wafer processes) deposition of rare earth material. The lasing wavelength is all wrong (1.9 um). It requires a pump laser in the 1.6 um range which is the usual range of interest. The efficiency is not very good. Couldn’t find the linewidth while scanning rapidly. It’s a run of the mill academic paper. There exist commercial electrically pumped lasers on silicon that are being continuously improved through different approaches. Intel is one of the leaders on that.

dogber1 5y ago
And on top of that, you can make almost any material lase. There have been entertaining experiments where folks used yogurt, apple juice, hair dye, and other fun liquids in pumped lasers, exploiting some molecular band transition that was accidentally good enough.
fanzhang 5y ago
Is there not a single dimension in which the paper is novel? If not, it seems like a mistake to publish this.
- echelon 5y ago
  Not my area of expertise, but something can be academically novel and interesting without having any commercial or industrial applicability.
- amelius 5y ago
  Isn't this what usually happens when the PR department of a university runs away with a story?
- redmare80 5y ago
  It's novel, it's a huge iteration in the space. But, it's also being misrepresented as more significant than it is due to the summary being friendly to laypeople.
- 908B64B197 5y ago
  Not really. It's a different approach with different tradeoffs that are just as bad as the previously known ones. That's probably why it wasn't picked up by a better journal and that nobody outside of the university where it happened is talking about it.
  - joeberon 5y ago
    Laser and Photonics Reviews is an excellent journal
rob_c 5y ago
Thanks for the review. Unfortunately knowing universities this read a little too much like a puff piece. Of the same article was on a news site I'd then go looking for their dept website. When they publish this themselves my reaction is a little more sceptical and glib unfortunately.
kragen 5y ago
Hmm, couldn't you do the doping as the last processing step? Can you switch the laser with on-chip electronics, even if you can't pump it electrically? 1.9 um sounds like it would be just fine for communications. (I haven't read the paper, just the PR fluff.)
hanniabu 5y ago
> This is neither low cost nor commercially relevant. That's the case for a lot of research. It paves the way to be iterated on.

dogber1 5y ago

And on top of that, you can make almost any material lase. There have been entertaining experiments where folks used yogurt, apple juice, hair dye, and other fun liquids in pumped lasers, exploiting some molecular band transition that was accidentally good enough.

fanzhang 5y ago

Is there not a single dimension in which the paper is novel? If not, it seems like a mistake to publish this.

echelon 5y ago
Not my area of expertise, but something can be academically novel and interesting without having any commercial or industrial applicability.
amelius 5y ago
Isn't this what usually happens when the PR department of a university runs away with a story?
redmare80 5y ago
It's novel, it's a huge iteration in the space. But, it's also being misrepresented as more significant than it is due to the summary being friendly to laypeople.
908B64B197 5y ago
Not really. It's a different approach with different tradeoffs that are just as bad as the previously known ones. That's probably why it wasn't picked up by a better journal and that nobody outside of the university where it happened is talking about it.
- joeberon 5y ago
  Laser and Photonics Reviews is an excellent journal

rob_c 5y ago

Thanks for the review. Unfortunately knowing universities this read a little too much like a puff piece. Of the same article was on a news site I'd then go looking for their dept website. When they publish this themselves my reaction is a little more sceptical and glib unfortunately.

kragen 5y ago

Hmm, couldn't you do the doping as the last processing step? Can you switch the laser with on-chip electronics, even if you can't pump it electrically? 1.9 um sounds like it would be just fine for communications. (I haven't read the paper, just the PR fluff.)

hanniabu 5y ago

> This is neither low cost nor commercially relevant. That's the case for a lot of research. It paves the way to be iterated on.