5 ms·

First Optical Rectenna Converts Light Directly to DC Current

35 points by jcr 11y ago

unwind 11y ago
Lots of dupes of this story recently, https://news.ycombinator.com/item?id=10305226 https://news.ycombinator.com/item?id=10305226 seems to be the oldest but there are a few more.
- jcr 11y ago
  Yes, there have been four link-bait web-spam regurgitations of this story submitted to HN. Some of them needed to have their titles edited by HN moderators due to link-bait. None of them linked to the original source, and none of them got much attention on HN. The HN Guidelines [1] ask us to avoid link-bait and submit original sources. The HN FAQ [2] says a few reposts are tolerable if a story hasn't gotten significant attention in the last year. https://news.ycombinator.com/item?id=10309752 https://news.ycombinator.com/item?id=10309752 6 points - 2 comment - phys.org https://news.ycombinator.com/item?id=10309647 https://news.ycombinator.com/item?id=10309647 3 points - 0 comment - www.sciencealert.com https://news.ycombinator.com/item?id=10307099 https://news.ycombinator.com/item?id=10307099 2 points - 0 comment - www.gizmag.com https://news.ycombinator.com/item?id=10305226 https://news.ycombinator.com/item?id=10305226 2 points - 1 comment - www.electronics-lab.com The claimed/potential efficiency numbers may never come to pass, but if they just get close, it's important new research for solar power and was interesting enough news to warrant an intentional repost. The submitted story is the "original source" press release from the Georgia Institute of Technology (gatech.edu). Though it has quotes from the authors of the research and is written at a high level, it's still just a press release about recently published research [3], so it's not entirely "original" per se. None the less, the press release is still more easily readable for most people than the research paper itself. The paper is Open Access (i.e. free) and DOI linked in the press release. Unfortunately, it's extremely common for sites like electronics-lab.com, eetimes.com, phys.org, sciencealert.com, gizmag.com and countless others to take original source press releases from university news sites, and create link-bait web-spam regurgitations. The majority of the supposed "articles" on such sites are just reproductions of press releases from other original sources, usually universities. Though universities are complicit in creating web-spam by allowing their press releases to be replicated, it's still better for new research to get some exposure. If you see a HN submission from one of the press release regurgitation mills, track down the original source and post it in a comment so the mods can change the url. It helps keep the quality of HN high. [1] https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html [2] https://news.ycombinator.com/newsfaq.html https://news.ycombinator.com/newsfaq.html [3] "A carbon nanotube optical rectenna" (Nature Nanotechnology, 2015). http://dx.doi.org/10.1038/nnano.2015.220 http://dx.doi.org/10.1038/nnano.2015.220
- dang 11y ago
  In addition to jcr's thorough response, I'll add that we don't officially consider reposts to be dupes until the story has had significant attention here. Otherwise the randomness of /newest is too brutal. I wrote about this here if anyone is interested: https://news.ycombinator.com/item?id=9828818 https://news.ycombinator.com/item?id=9828818.
hliyan 11y ago
RF rectennas apparently already have efficiencies up to 90%. According to this article, improving the fabrication process could lead to optical efficiencies up to 40%. That's double the efficency of any photovoltaic cell available today.
- mapt 11y ago
  Not all variants. https://en.wikipedia.org/wiki/Solar_cell_efficiency#/media/File:PVeff(rev150806).jpg https://en.wikipedia.org/wiki/Solar_cell_efficiency#/media/F...
magic_man 11y ago
I thought they already had photo voltaic cells. I guess this is just a more efficient version of a device like that. It made it sound like they had invented a photo voltaic cell which they didn't.
- hatsunearu 11y ago
  This is huge because it has potential (hah) to become an ultra high speed photodetector, which have numerous uses in the industry. Conventional photodetectors are essentially transparent photodiodes, and you have to pass a constant current through them for them to work, which generates heat and is generally a bad side effect. Antennas on the other hand are completely passive and therefore immune to heat related issues. Also, unlike photodiodes and semiconductor devices, antennas are completely linear. Nonlinearities cause distortion that limit usable bandwidth.

35 points by jcr 11y ago

Lots of dupes of this story recently, https://news.ycombinator.com/item?id=10305226 https://news.ycombinator.com/item?id=10305226 seems to be the oldest but there are a few more.

jcr 11y ago
Yes, there have been four link-bait web-spam regurgitations of this story submitted to HN. Some of them needed to have their titles edited by HN moderators due to link-bait. None of them linked to the original source, and none of them got much attention on HN. The HN Guidelines [1] ask us to avoid link-bait and submit original sources. The HN FAQ [2] says a few reposts are tolerable if a story hasn't gotten significant attention in the last year. https://news.ycombinator.com/item?id=10309752 https://news.ycombinator.com/item?id=10309752 6 points - 2 comment - phys.org https://news.ycombinator.com/item?id=10309647 https://news.ycombinator.com/item?id=10309647 3 points - 0 comment - www.sciencealert.com https://news.ycombinator.com/item?id=10307099 https://news.ycombinator.com/item?id=10307099 2 points - 0 comment - www.gizmag.com https://news.ycombinator.com/item?id=10305226 https://news.ycombinator.com/item?id=10305226 2 points - 1 comment - www.electronics-lab.com The claimed/potential efficiency numbers may never come to pass, but if they just get close, it's important new research for solar power and was interesting enough news to warrant an intentional repost. The submitted story is the "original source" press release from the Georgia Institute of Technology (gatech.edu). Though it has quotes from the authors of the research and is written at a high level, it's still just a press release about recently published research [3], so it's not entirely "original" per se. None the less, the press release is still more easily readable for most people than the research paper itself. The paper is Open Access (i.e. free) and DOI linked in the press release. Unfortunately, it's extremely common for sites like electronics-lab.com, eetimes.com, phys.org, sciencealert.com, gizmag.com and countless others to take original source press releases from university news sites, and create link-bait web-spam regurgitations. The majority of the supposed "articles" on such sites are just reproductions of press releases from other original sources, usually universities. Though universities are complicit in creating web-spam by allowing their press releases to be replicated, it's still better for new research to get some exposure. If you see a HN submission from one of the press release regurgitation mills, track down the original source and post it in a comment so the mods can change the url. It helps keep the quality of HN high. [1] https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html [2] https://news.ycombinator.com/newsfaq.html https://news.ycombinator.com/newsfaq.html [3] "A carbon nanotube optical rectenna" (Nature Nanotechnology, 2015). http://dx.doi.org/10.1038/nnano.2015.220 http://dx.doi.org/10.1038/nnano.2015.220
dang 11y ago
In addition to jcr's thorough response, I'll add that we don't officially consider reposts to be dupes until the story has had significant attention here. Otherwise the randomness of /newest is too brutal. I wrote about this here if anyone is interested: https://news.ycombinator.com/item?id=9828818 https://news.ycombinator.com/item?id=9828818.

hliyan 11y ago

RF rectennas apparently already have efficiencies up to 90%. According to this article, improving the fabrication process could lead to optical efficiencies up to 40%. That's double the efficency of any photovoltaic cell available today.

mapt 11y ago
Not all variants. https://en.wikipedia.org/wiki/Solar_cell_efficiency#/media/File:PVeff(rev150806).jpg https://en.wikipedia.org/wiki/Solar_cell_efficiency#/media/F...

magic_man 11y ago

I thought they already had photo voltaic cells. I guess this is just a more efficient version of a device like that. It made it sound like they had invented a photo voltaic cell which they didn't.

hatsunearu 11y ago
This is huge because it has potential (hah) to become an ultra high speed photodetector, which have numerous uses in the industry. Conventional photodetectors are essentially transparent photodiodes, and you have to pass a constant current through them for them to work, which generates heat and is generally a bad side effect. Antennas on the other hand are completely passive and therefore immune to heat related issues. Also, unlike photodiodes and semiconductor devices, antennas are completely linear. Nonlinearities cause distortion that limit usable bandwidth.