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UV Nanolasers From ZnO Nanowires
The Evil Dwarf from Hell writes: "This weeks Science has an article on ZnO nanowire base UV lasers, abstract ( paid subscritption required for article). The 70 to 100 nm diameter wires lase at 386nm, line width .3 nm. The growth takes place on a thin Au film on a sapphire surface, and the wires reach lengths of 2 to 10 m. What makes this lasing unusual is it occurs without the use of mirrors. Apparently ZnO forms a natural lasing cavity. (The lasing is optically pumped from a Nd:YAG laser)." The link above is registration-required, but there's another article which describes the whole process.
I want Microsoft bashing. I want software release notices. I want anti-big-industry rants. I want free software cheerleading.
How am I supposed to follow the party line if real News for Nerds and Stuff that matters shows up here?
Your link to the other article seems to be dead, but I imagine it was the one about TB/cm^3 storage using femto-second lasers and spectral hole burning. Someone commented then that fs lasers are huge power hungry monsters. A day ro so after reading that I passed a poster display from some of our physics grad students, who now have a suitcase sized, battery powered, fully portable femto-second laser.
I doubt the ZnO lasers will get down to femto-second pulse lengths very soon though, it is rather a specialized trick that they use to get pulses that short.
Note to slashdot editors: if you value your readers' time, please expand all but the most common acronyms or abbreviations the first time you use them, even if you are quoting an email that you received. For example, the article that does not require registration does not mention an "Nd:YAG laser" and very cursory search on google did not turn up a definition (although it did find references to the term).
Electronics in the 20's are NOT what they are today.
I'm not saying some exorbitant journal prices are justified, only that the peer review process IS important, though it has it's faults.
I'd rather see every insititution, especially any using public money have to publish all articles, for free, to everyone, on the net. Other 'journals' or peer review boards can link in articles they see as relevant to the state of the art. This also allows many researchers to benefit from each other's work.
The peer review costs money.
The peer review costs money.
Not as much as you might think. We reviewers aren't paid for the reviews: it's regarded as part of our professional responsibility. (The same happens with grant reviews: the vast majority is done by other scientists.)
Many journals charge money to print articles, others charge literally thousands of dollars/year for a subscription. This is a huge bone of contention on many campuses: Professor A and B want the Journal of Obscure Latvian Chemistry at $2000/year, but C and D would rather have Acta Trivia at $2500/year. Academic budgets aren't much- what do you do?
Science and Nature are special cases: there's significant editorial comment in each, and so the costs of printing them are much higher. (The first 3rd of each is quite understandable by any interested layman.)
So why not go electronic? Simple: electronic reserves have a miserable record of longevity. I can and have looked up articles from 1920, and that's hardly the limit. We can't read electronic Pioneer data from the 1960s.
Keeping old journal articles in a format that's always readable is going to cost, and cost big. You'll need multiple servers so that a single crash doesn't kill you, and sysadmins to care for the machines, bandwidth costs, plus format conversion.
And of course, you'll still need to pay for the staff to handle sending articles around for peer review.
Stanford has a program that's looking into solving some of these problems with a distributed system, but it's going to be a long, long time before we abandon paper.
Eric
"Seven Deadly Sins? I thought it was a to-do list!"
Who wrote this? Michael or Geordi LaForge?
Simple. In the interest of academic freedom, scientific journals (as opposed to magazines like science news) do not print advertisments, thus the entire cost of publication is borne by the authors and/or subscribers.
Many articles in physics appear on xxx.lanl.gov before they a published. However, these are pre-print drafts that haven't been peer reviewed or selected in any other way. Many, many of the articles published there are Just Plain Wrong. When you pay for a peer reviewed journal, you are paying for a lower (though not zero) probability of something being totally wrong.
That isn't to say that publication costs are not a major source of contention. Obviously, scientists want as wide of a distribution as possible, and university library budgets, especially at smaller schools is limited. Some journals Nature are real assholes about this sort of thing, others are not so bad, but in the end, someone needs to pay the bills.
Many researchers post some or all of their published papers in PDF format on their webpages, but journals differer on if, how, and when you are allowed to do so.
Wait a minute here! Zinc Oxide is the stuff you use to keep damaging UltraViolet sunlight off your face. Now they're using it to turn it into UV Lasers? I can feel my nose burning already. Ouch!
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Not quite. The physical size of the lasing device is irrelevant; all that matters (WRT putting data on a surface) is the light coming out of it.
Any decent laser can be used to produce an incredibly thin beam, such that the limiting factor becomes the wavelength of the light. This is the reason for all the brouhaha over blue lasers - nothing to do with the physical size of the laser, but the fact that using a smaller wavelength allows you to pack more data on the surface.
Now, physical dimensions aside, these *are* UV, so clearly they're short-wavelength lasers, but IIRC the blue lasers are around 460nm (is that right?) so a 386nm UV would allow for roughly 42% more data to be packed on a given surface.
Of course, use of UV lasers in home electronics devices could be *really* dangerous, because if you somehow looked into the laser you wouldn't even realize it until you noticed the irreparable damage to your retina.
ZFS: because love is never having to say fsck
--Fesh
--Fesh
Kill -9 'em all, let root@localhost sort 'em out.
These people looked deep into my soul and assigned me a number based on the order in which I joined.
Nah, it would just be usual stuff by the time it happens...
Technology is only cool untill it's available. Then it becomes daily life and nobody cares unless it stops working.
Do you daily think about how incredibly cool it is to have a computer thousand times more powerful than computers 50 years ago in your pocket? Having a cell-phone? Running a multi-user OS on your PC? Crossing the atlantic ocean in less than 8 hours? Using satellites for mass communication? Being able to cure almost any decease that used to kill people before they reached 40 just a few hundred years ago? Manipulating the genetic code in plants and animals? Paying with plastic cards? Controlling nuclear energy? Drilling for oil hundreds of meters below the seabed? Surfing and communicating worldwide on the Internet? Driving your own car? Having automated appliances in your house doing your laundry and dishes? We live in an incredibly advanced world, it's just that because things become commonplace we stop seeing the wonders technology already performs for us.
No, it's not the size of the laser that matters for data density, it's the wavelength.
However, if they are 100 times smaller (and cheaper) you could put a hundred of them into your device of choice to improve data throughput and access time (even if they can't be controlled independently, there would still be much less head-movement).
If the wavelength is 100th of currently used systems, then the area of pits on a cd type system can be 10,000th of the size, so that data densities could be 10,000 tims as great. Near UV light is actually about 1/3rd the wavelength of green light. However, UV photons also have 3 times as much energy, so the disc used would heat up more, and have to be stable against this, which would quite difficult for Write operations (assuming everything keeps the same as CD-RW).
The real power of these lasers for data storage may be in holographic systems, as there may be a way to store phase information at UV frequencies that can't be used for visible lasers. Holographic techniques would also allow data densities to scale as wavelength^-3, so that going from green to UV would give 27 times the data density (which is already estimated at 10Tb for 1 cubic inch in visible light systems)
And in the field of photonics and optical computing, cheap bright lasers are essential.
/., you've finally found a story that can be used for something practical. Now my only question is, how long until 10 TB drives ship?
Yang said that at this preliminary stage of development, the nanolaser is comparable to or better than the gallium nitride blue laser in terms of ease of manufacture, brightness and much smaller dimensions.
"It basically has high enough intensity to think about making a practical device," he said. Plus it operates at room temperature.
Congratulations
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Shoudn't this kind of research, mostly funded by with government money, be published in free foruns?
I understand paper and ink costs money, and atm-links also cost, but this kind of public-funded research should be made freely available to the interested public, besides perhaps being published in "reference magazines".
You cannot proceed from the informal to formal by formal means
Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.
...lots of research just as interesting as this gets published all the time. ZnO is a wide-bandgap material enjoying a renaissance of interest, and might compete with SiC, DLC, and GaN, but I'm not sure this is worthy of a full-blown /. article. Now combinatorial MBE to explore the TiO2:Co system, that was /. worthy ;-)
"Daddy, will galium arsenide and arsenic acid spills stop from that bad-chip-industry?"
"Yes, kids. It'll stop. Now, put your nose back to your face, and go to school."
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Hmmm...
First a quote:
*begin quote from the article (UniSci's)*
Though Yang now must use another optical laser to excite the zinc oxide molecules so that they will emit UV light -- a process called optical pumping -- he hopes eventually to "pump" the zinc oxide with electrons. Electron pumping is necessary for a laser to be integrated into an electronic circuit.
*end quote*
Now then, once they're capable of electron-pumping, you'll have an incredibly small laser (which, most likely can be pumped by miniscule--comparatively--voltages). This will probably involve growing the lasers in place on something that later is etched as the circuit to provide the electrons.... So you'll have an incredibly small solid state UV laser.... I don't know what the characteristics of the laser are (especially the firing time), but it'd be entertaining if they could be fired in the short enough pulses to allow the kind of storage this other article talked about
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:Backstab >KILLS< god.
If these new lasers are 100 times smaller than the old ones, would I be correct in guessing that the optical discs resulting from this new technology would store 100 times more data (or maybe 10000 times, if it works in two dimesions)? How long then, would it be before such discs could replace your old hard disks?
One day, you know, this miniaturisation will just stop... there has to be a limit to it.