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After 60 Years, a Room-Temperature Maser

Soulskill posted about 2 years ago | from the cool-and-yet-not-cool dept.

Science 102

gbrumfiel writes "Before there were lasers, there were masers: systems that amplified microwaves instead of light. Solid state masers are used in a variety of applications, including deep space communication, but they've never been as popular as lasers, in part because they have to be cooled to near absolute zero in order to work. Now a team of British physicists have built a room-temperature maser using some spare chemicals and a laser they bought off of eBay. The new device is 100 million times as powerful as existing masers and might revolutionize telecommunications."

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102 comments

revolutionize eh? (0)

Anonymous Coward | about 2 years ago | (#41002453)

then give it out freely and let man really use it wickedly

Re:revolutionize eh? (1)

SnarfQuest (469614) | about 2 years ago | (#41002641)

Isn't this something every evil scientist has in his laboratory already? I've got two!

Re:revolutionize eh? (0)

Anonymous Coward | about 2 years ago | (#41003225)

Not every evil scientist. Some of us make do with regular masers attached to freezerays.

Re:revolutionize eh? (0)

Anonymous Coward | about 2 years ago | (#41007847)

Now those in turn could be attached to the heads of polar bears!

Re:revolutionize eh? (1)

Anonymous Coward | about 2 years ago | (#41010783)

It's not a death ray or an ice beam - that's all Johnny Snow.

Wow. (-1)

Anonymous Coward | about 2 years ago | (#41002463)

wow.

Room-Temperature Masers (-1, Redundant)

Ol Biscuitbarrel (1859702) | about 2 years ago | (#41002475)

Mounted to frickin' lark's heads.

[/pinky in mouth]

Re:Room-Temperature Masers (0)

Anonymous Coward | about 2 years ago | (#41021661)

More like Turtles with frikkin' Masers.
[S->T; L->M]

Cold Fusion? (-1, Troll)

Soporific (595477) | about 2 years ago | (#41002499)

Why does this remind me of so many cold fusion stories I've seen?

~S

Re:Cold Fusion? (5, Informative)

cjc25 (1961486) | about 2 years ago | (#41002663)

Because you saw the words "room-temperature" and you missed the last sentence of the first paragraph where it says the findings were published in one of the most widely respected peer reviewed journals?

Or just didn't read TFA ;)

Re:Cold Fusion? (-1, Flamebait)

Soporific (595477) | about 2 years ago | (#41002899)

This is Slashdot, of course I didn't read the article and no idea what the journals credibility is either.

~S

Re:Cold Fusion? (1)

chris mazuc (8017) | about 2 years ago | (#41003043)

no idea what the journals credibility is either.

You've never heard of Nature?

Re:Cold Fusion? (0)

Anonymous Coward | about 2 years ago | (#41003151)

Nature, is that the stuff outside my window?

Re:Cold Fusion? (1)

Anonymous Coward | about 2 years ago | (#41003301)

Your mom's basement has a window?

Re:Cold Fusion? (4, Funny)

drkim (1559875) | about 2 years ago | (#41005821)

Your mom's basement has a window?

Well, it's 'technically' a poster of two girls standing on the beach... not a real window.

Re:Cold Fusion? (0)

Anonymous Coward | about 2 years ago | (#41007599)

Is it really a poster of two girls, not women? I bet the lack of boobs tricked you into the faulty behaviour of wondering about nature. Ask your mom to exchange it so you can concentrate on the bare essentials.

Re:Cold Fusion? (0)

Anonymous Coward | about 2 years ago | (#41008291)

Of course. True nerds don't like Windows. :-)

Re:Cold Fusion? (1)

prezkennedy.org (786501) | about 2 years ago | (#41004497)

Reading sure is hard isn't it? Maybe you should head back on over to Digg... Oops...

Re:Cold Fusion? (1)

Soporific (595477) | about 2 years ago | (#41007725)

It sure is, especially on your blog. I love it! Matt for President!!! Oops...

Hah, that was funny wasn't it? If only I had your Maser like wit.

~S

Re:Cold Fusion? (0)

Anonymous Coward | about 2 years ago | (#41004719)

I didn't read the article and no idea what the journals credibility is either.

You don't know what the credibility of Nature is? The door is that way, kid. Do let it hit you on the arse on your way out.

Re:Cold Fusion? (1)

Soporific (595477) | about 2 years ago | (#41007733)

You are ruining the credibility of the elderly there AC.

~S

Re:Cold Fusion? (0)

Anonymous Coward | about 2 years ago | (#41005221)

The Arsenic in DNA instead of Phosphorus was published in "Science", another widely respected journal.

Re:Cold Fusion? (0)

Anonymous Coward | about 2 years ago | (#41002883)

"In the long term it could find a use in communications, but it first needs to be refined."

Details, details ...

Re:Cold Fusion? (3, Insightful)

geekoid (135745) | about 2 years ago | (#41002891)

Because you are a knee jerk moron who can't actual read the entire description, much less the article, before pounding your meat hooks into your key board in some vain attempt at a brow furrowing thought?

Re:Cold Fusion? (-1, Flamebait)

Soporific (595477) | about 2 years ago | (#41002937)

Do you feel better now?

~S

Re:Cold Fusion? (0)

geekoid (135745) | about 2 years ago | (#41003179)

I'll never feel better as long as lazy, ignorant opinionated fools keep spouting nonsense and not be called on it.
so, no.

Re:Cold Fusion? (-1, Offtopic)

Soporific (595477) | about 2 years ago | (#41003231)

Well, fuck you too then.

~S

Re:Cold Fusion? (5, Funny)

symbolset (646467) | about 2 years ago | (#41003859)

You may be destined for a long unpleasant online experience.

Re:Cold Fusion? (1)

interkin3tic (1469267) | about 2 years ago | (#41006297)

It's okay, we've all said stupid stuff online before and regretted it. I really wish slashdot had an option to moderate your own posts down to "-2: redacted".

Or I wish I just stopped putting my foot in my mouth. That might be better.

Re:Cold Fusion? (0)

KaInDaWg (115890) | about 2 years ago | (#41003103)

You Mad Bro?

Re:Cold Fusion? (0)

Anonymous Coward | about 2 years ago | (#41003083)

Because you didn't read the article?

Cue the Mesmetron apocalypse (-1)

Anonymous Coward | about 2 years ago | (#41002529)

How long until we get something along these lines [youtube.com] ?

pffff! (0)

cynop (2023642) | about 2 years ago | (#41002583)

...let me know when they make a working room-temperature faser.

Staff Weapon! (0)

Anonymous Coward | about 2 years ago | (#41002635)

Does this mean I can have my very own Goa'uld staff weapon yet?

Re:Staff Weapon! (1, Insightful)

lister king of smeg (2481612) | about 2 years ago | (#41003613)

i'd rather have a zat'nik'tel

Not the first room temperature maser (1)

Anonymous Coward | about 2 years ago | (#41002661)

While this may be the worlds' first room-temperature solid-state maser, it certainly isn't the first room temperature maser. Standard hydrogen masers (the ones that help NIST tell what time it is) are certainly not cryogenic.

Re:Not the first room temperature maser (2)

game kid (805301) | about 2 years ago | (#41002889)

Ah, but does that use a laser they bought off of eBay?

No? Then *yawn*.

I mean, just imagine what the British team can do with a laser they bought off of craigslist or backpage.

Re:Not the first room temperature maser (1)

teridon (139550) | about 2 years ago | (#41009355)

Can hydrogen masers amplify any frequency? I admit I know next to nothing about them, but I was under the impression they could only amplify at the resonant frequency of hydrogen (e.g. see http://tf.nist.gov/general/enc-h.htm [nist.gov] )?

Re:Not the first room temperature maser (0)

Anonymous Coward | about 2 years ago | (#41019225)

Well, a rubidium maser can produce signal at different frequencies. I'm sure that there are masers that use other transitions as well.

Absolute Zero (5, Insightful)

Anonymous Coward | about 2 years ago | (#41002879)

Just to nitpick a bit, 10 K (as the article mentions) is really quite easy to achieve with off-the-shelf cryogenic equipment, and not the "near absolute zero" as the summary sort of suggests (I usually reserve this for 1 K, but maybe this is just me).

Re:Absolute Zero (5, Funny)

hamster_nz (656572) | about 2 years ago | (#41003633)

Must be just you...

* When I need a hat on it's cold

* When my beer in the truck freezes overnight then it's really cold

* When the diesel in my truck freezes overnight then it's really cold.

* When my desktop maser works without any external cooling, then it's near absolute zero.

Re:Absolute Zero (2)

trout007 (975317) | about 2 years ago | (#41003935)

When my Helium has a positive JT coefficient it's really cold.

Re:Absolute Zero (1)

Grog6 (85859) | about 2 years ago | (#41005021)

It always struck me as strange how you can use liquid nitrogen to help recondense liquid helium; the little sterling engine makes the coolest noise...

Re:Absolute Zero (4, Informative)

Yvanhoe (564877) | about 2 years ago | (#41007937)

Just to elaborate :

- Liquid nitrogen boils at 77 K (â'196 ÂC; â'321 ÂF), it is very cheap and a hobbyist can get this easily.
- Liquid helium boils at 3-4 K and is also produced industrially.
If you have something that requires a low temperature but no lower than 77K, it is very easy : just dip it in liquid nitrogen.
If you have something that requires 10K, it is "easy" also : put it into liquid helium.
I think it is fair to say that "near absolute zero" is a sentence that supposes heavy cryogenic installations. 10 K is far easier than that.

Liquid N2 vs. H2 vs. He vs. 10K (1)

billstewart (78916) | about 2 years ago | (#41016687)

Yes, you can use liquid helium to cool it, and it's probably easier than running your own cryogenic cooling pumps. But unfortunately it's not cheap - it's about $10/liter, vs. less than $1/liter for liquid hydrogen or $0.10 for liquid nitrogen. And there's a limited supply of helium in the world, so it's likely to be getting more expensives. (Liquid H2 temperature is about 20K, so it's not quite enough for a maser that needs to be 10K.)

Room-temperature masers are much more practical. And they're a lot easier to attach to sharks.

Re:Liquid N2 vs. H2 vs. He vs. 10K (1)

Yvanhoe (564877) | about 2 years ago | (#41030911)

You have to admit that having to attach a cryogenic system on the shark also has a touch to it, too...

Re:Absolute Zero (4, Interesting)

TubeSteak (669689) | about 2 years ago | (#41004621)

You know what's better than having to use off-the-shelf cryogenic equipment?
Not having to use it.

IMO, this is the real news:

He came across a decade-old publication by Japanese researchers [cas.org] suggesting that when the electrons in pentacene are excited by a laser, they configure such that the molecule could work as a maser, possibly even at room temperature.

I wonder how many other scientific breakthroughs are just sitting around waiting for anyone to conduct basic followup on a research paper.

Re:Absolute Zero (2)

mdielmann (514750) | about 2 years ago | (#41006379)

If only scientists were paid to review other scientists' work, replicate it, and maybe build upon it. But that doesn't get you grant money, usually. That's more often reserved for new work or application, it seems.

Re:Absolute Zero (1)

CurryCamel (2265886) | about 2 years ago | (#41007563)

Well, this guy did it. And I bet he now has no problems getting more funding. That is point of reserving money for new work - you don't know what you might get, when building on other people's work you get the benefit of hindsight.

Re:Absolute Zero (0)

Anonymous Coward | about 2 years ago | (#41007695)

You must be joking. The problem is generally believed to be the exact opposite. The publish or perish culture combined with a refusal to accept risk of failure has been bemoaned to result in most academic work being dedicated to the safe option of incremental progression on the work of others. This translates in to a depressingly slow rate of innovative and groundbreaking research.

Re:Absolute Zero (0)

Anonymous Coward | about 2 years ago | (#41006387)

Don't get me wrong, I think this is awesome! I work in a lab where we do often go to "near absolute zero" and would kill for the same phenomena to work at ~10K (it's easy!). As far as applications go, yes you don't want to use 50+ K worth of cryogenic equipment that requires constant maintenance and extremely inefficient operation. Physorg has more info on the cool applications: http://phys.org/news/2012-08-maser-power-cold-demo-solid-state.html .

Re:Absolute Zero (4, Informative)

Yvanhoe (564877) | about 2 years ago | (#41007955)

I wonder how many other scientific breakthroughs are just sitting behind paywalls waiting for anyone to conduct basic followup on a research paper.

Here, fixed that for you. As a CS professional and biology hobbyist, I once decided to use my free time to get a specialization in gerontology genomics and to help open source projects in bioinformatics. I then discovered that 90% of the papers in the field are behind paywalls that even some universities can't access. I needed to read maybe 100-200 papers to have a good view of the field. At 25$ each, it made it expensive to volunteer freely for research projects...

Re:Absolute Zero (1)

bill_mcgonigle (4333) | about 2 years ago | (#41020807)

I wonder how many other scientific breakthroughs are just sitting around waiting for anyone to conduct basic followup on a research paper.

And that in the subsequent decade the Japanese researchers didn't do what these guys did. Strange, they'd probably have a compelling business in operation by now.

Re:Absolute Zero (1)

Arabian Nights (2597797) | about 2 years ago | (#41006071)

To be fair, I don't think your arbitrary distinction is any better than theirs. It sound ridiculous, but in my work I consider anything warmer than 0.4 K "warm" because of how much technology and engineering you need to to best it (working on a dilution refrigerator). I'm sure there is someone working with nuclear demagnetization who balks at my standard, too.

Accepting that, I think it's perfectly fine for the public to refer to 10 K as "nearly absolute 0" because on the typical public-used temperature scale (e.g., for weather), 10 K is unfathomable.

but can you mount it in sharks' heads? (-1, Redundant)

swschrad (312009) | about 2 years ago | (#41002907)

isn't really truly evil unless you can.

Re:but can you mount it in sharks' heads? (0)

Anonymous Coward | about 2 years ago | (#41003065)

If they are kept at room temperature.

Powered by... (4, Funny)

Anonymous Coward | about 2 years ago | (#41002951)

"Using spare chemicals, a laser bought on eBay and angst from a late-night argument, physicists have got the world's first room-temperature microwave laser working."

Getting this to work reliably is going to require a reliable source of angst. Any high school should do the trick.

Re:Powered by... (2)

rwven (663186) | about 2 years ago | (#41003051)

The most annoying thing about this is that the dude had it built for three days and refused to turn it on out of fear of failure. Kudos for getting it done and a slap for being a wuss about it.

Re:Powered by... (1)

Zan Lynx (87672) | about 2 years ago | (#41003685)

I'm like that whenever I buy a new computer part. Sometimes it sits in the box for weeks.

Re:Powered by... (1)

camperdave (969942) | about 2 years ago | (#41003957)

When the difference between success and failure is the difference between microwaving the Jiffy-Pop while it is still in the cupboard, and the expression "Ow! My sperm!", I'd be hesitant as well.

Re:Powered by... (1)

rwven (663186) | about 2 years ago | (#41004303)

RTFA. He didn't turn it on because he was nervous it wouldn't work...

Re:Powered by... (0)

Anonymous Coward | about 2 years ago | (#41004989)

Exactly! Wouldn't work... as in, instead of a nice coherent beam focussing on some popcorn, it sprays radiation all over the place, inflicting bodily harm to something that should never, ever be microwaved.

One Whoosh for you.

Conservation of angst (1, Insightful)

bigtrike (904535) | about 2 years ago | (#41003303)

This may drain all of the angst out of the entire school, altering youth forever.

Re:Powered by... (1)

lister king of smeg (2481612) | about 2 years ago | (#41003643)

So if it is powered off of angst does that mean we can power it off of twilight dvd's and books?

Re:Powered by... Creme Brule?!? rtfa (1)

j-stroy (640921) | about 2 years ago | (#41003745)

Now this is my sort of science! I expect that this discovery has been made several times before with a predictable outcome; hence its "undiscovered" status.

Re:Powered by... (1)

c0lo (1497653) | about 2 years ago | (#41009841)

Getting this to work reliably is going to require a reliable source of angst. Any high school should do the trick.

TFA:

The final impetus came from an argument with his wife.

Seems like the problem has been taken care.

Super Wow (2, Interesting)

Anonymous Coward | about 2 years ago | (#41003063)

This is frikken huge news, if it pans out. I'm old enough to remember when news of the first MASERs came out. Before LASERs.
    Just the applications alone in Atomic Spectroscopy, ECR technology, high power communications- do you realize just how sloppy the frequency spread of Klystrons and similar devices are? Accelerator Technology, space charge cooling,... the implications for Fusion research...
    Super Wow.
    If it pans out.

Re:Super Wow (1)

m6tt (263581) | about 2 years ago | (#41005373)

This could be great for p2p 802.11 links of some kind as well...I wonder if having the beam coherent would have any effect on things like rain and fog effects...

Neat, but..... (0)

Anonymous Coward | about 2 years ago | (#41003087)

Neat, but generating high power, coherent microwaves is pretty simple now, not so before III-V semiconductors. I have read about their usefulness for space power beaming.

A microwave 100 million times more powerful? (1, Funny)

Anonymous Coward | about 2 years ago | (#41003097)

This is a thread I'll get my popcorn for.

Re:A microwave 100 million times more powerful? (0)

Anonymous Coward | about 2 years ago | (#41004033)

You get the popcorn and sneak it into Hathaway's house. I'll get the target coordinates computed for trajectory adjustment.

With a tracking magnetic mirror (1)

Anonymous Coward | about 2 years ago | (#41003453)

... you could vaporize a man sized object from space...

Re:With a tracking magnetic mirror (0)

Anonymous Coward | about 2 years ago | (#41003795)

Or write half your name on the moon before some freakazoid comes and stops you?

I want diagrams, temperatures, power figures, etc. (0, Redundant)

Wierdy1024 (902573) | about 2 years ago | (#41003689)

Considering this is Nature, the lack of any numbers, or even a link to a paper are very disappointing. The writing style itself makes it sound like they've just turned lead into gold as well...

I want diagrams, temperatures, power figures, etc. Not waffle. I expect better.

Re:I want diagrams, temperatures, power figures, e (5, Informative)

Anonymous Coward | about 2 years ago | (#41003739)

Actually, the link to the proper paper is at the bottom in the references part, with a good description of results. Here is a direct link: http://www.nature.com/nature/journal/v488/n7411/pdf/nature11339.pdf

Re:I want diagrams, temperatures, power figures, e (2)

tyrione (134248) | about 2 years ago | (#41006975)

One demanding citations of work would expect to know to look in the citations section.

Like SimCity2000 (0, Insightful)

Anonymous Coward | about 2 years ago | (#41004711)

Here we unlock microwave power plants, next unlock is fusion so get excited!

Re:Like SimCity2000 (0)

Anonymous Coward | about 2 years ago | (#41006259)

Man I so wish that is true. 2050 here we come.

Re:Like SimCity2000 (1)

mister_playboy (1474163) | about 2 years ago | (#41008889)

That game taught me to not live near such a power plant.

You don't want to be near by when the satellite mis-aims it's beam...

room temperature maser is not novel (0)

Anonymous Coward | about 2 years ago | (#41005931)

For an example, this group was creating room-temperature masers in the mid-90's: http://walsworth.physics.harvard.edu/research/pastprojects/atomicclock.html

Re:room temperature maser is not novel (4, Insightful)

bmo (77928) | about 2 years ago | (#41007621)

But those aren't solid-state. This is.

That's why it's a breakthrough. Solid state laser diodes got us optical media, fiber optics, 3d scanners, etc, because they're not fragile, big, and expensive like gas lasers. Gas masers are big, expensive, and fragile and need specialized technicians to keep running. Solid state masers you can take out in the field. You can put them in a hand-held device. Plus it's cheap. Really cheap. I just looked up the cost of p-Terphenyl and it's $165 for 100 grams of scintillation grade. That's a lot of crystal, and the dopant is $64 for 100mg. While that's a lot more expensive than platinum, it's a dopant - you only need a tiny amount in a crystal, on the order of .05%. 100mg of dopant can tint 200g of p-Terphenyl.

Applications? It will revolutionize microwave comms and broadcast links. Microwave tower links are everywhere but the problem is there are so many and interference is a huge issue. A tower-to-tower maser link is not going to be as prone to spreading and causing interference and doesn't require the power of current microwave links. Broadcast and comms engineers are already salivating at the prospects. And that's just one application.

--
BMO

Re:room temperature maser is not novel (0)

Anonymous Coward | about 2 years ago | (#41008073)

One assumes that if it is as powerful as they claim, and that it scales, you could reasonably use a high power solid state maser to transmit a sensible amount of power from a geostationary solar array? Sim City 2000 here we come!

Re:room temperature maser is not novel (0)

Anonymous Coward | about 2 years ago | (#41008083)

You can put them in a hand-held device. Plus it's cheap.

Applications?

Medical Tricorder for all GPs! Stethoscopes go to history.

microwaves radiation is still light (1)

junglebeast (1497399) | about 2 years ago | (#41007429)

"most in the field gave up on masers and moved on to lasers, which use the same principles of physics, but work with optical light instead of microwaves."

what the hell? microwaves are still EM radiation. EM radiation is light. thus a maser is just a regular laser in a different wavelength, no more different from a green laser vs a red laser....which are also just different wavelengths of light.

Re:microwaves radiation is still light (0)

Anonymous Coward | about 2 years ago | (#41007677)

what the hell? microwaves are still EM radiation. EM radiation is light. thus a maser is just a regular laser in a different wavelength, no more different from a green laser vs a red laser....which are also just different wavelengths of light.

Except that that wavelength is critical, the wavelength is very different to in optical light. That means you get very different effects which is why masers are so desirable, but it's also why until now they've been so hard to make.

As an analogy green and red lasers are like green and red apples, while a maser's an orange. Ok they're all fruit, but the green/red apples are basically the same thing but the orange is something very different.

Re:microwaves radiation is still light (1)

Flipstylee (1932884) | about 2 years ago | (#41008563)

Mod parent up.

Re:microwaves radiation is still light (2)

lee1 (219161) | about 2 years ago | (#41009191)

I only see the term "maser" in popular accounts of science. In my experience the people who work on them call them "lasers", "free-electron lasers" (FELs), "microwave lasers", etc. And microwave lasers have been commonplace for decades in the form of FELs. What's new here is the "solid state" part.

Re:microwaves radiation is still light (0)

Anonymous Coward | about 2 years ago | (#41012455)

I only see the term "maser" in popular accounts of science.

There are 2000 references to masers in arXiv [arxiv.org] alone.

Re:microwaves radiation is still light (1)

danlip (737336) | about 2 years ago | (#41011671)

The quote says "optical light", which means the range visible to humans. The quote also says "the same principles of physics", which could easily be interpreted to mean "still EM radiation". So there is nothing wrong with that quote.

Re:microwaves radiation is still light (1)

Amouth (879122) | about 2 years ago | (#41011779)

actually.

optical light is a form of EM radiation
microwaves are form of EM radiation

optical light is not any form of microwave
microwaves are not any form of optical light

optical light is a defined band in the possible EM radiation wavelengths and so is microwaves, but the two defined bands do not at all intersect

Re:microwaves radiation is still light (1)

sjames (1099) | about 2 years ago | (#41015455)

You might notice given a cursory inspection that EM radiation at differing wavelengths can behave quite differently. So much so that the equipment really isn't interchangeable. That's why you don't see homebrew CT scans being done with overclocked keychain flashlights, for example. Likewise, you can't just crank the frequency knob on a ham transmitter and use it as an improvised security light.

Sweet... (1)

DaneM (810927) | about 2 years ago | (#41007441)

The next step seems to be a portable power supply...

= Maser Gun! Nice.

Good start, but let's rein in the enthusiasm a bit (2)

Muad'Dave (255648) | about 2 years ago | (#41009279)

It may be 100 Million times as strong as its predecessor, but in absolute terms it required 1.5 KILOWATTS of input power to generate 100 MICROWATTS of output power [nature.com] . Not the most efficient thing in the world - that's an input:output power ratio of 15 million:1 (nearly 72 dB).

Re:Good start, but let's rein in the enthusiasm a (0)

Anonymous Coward | about 2 years ago | (#41011003)

Yeah, but even if you had NO improvement and illuminated the crystal with a 30 dBm (1 watt) laser, let's see here. 30 dBm - 72 dB = -42 dBm. That's still a lot of power. Especially if you're beaming data in a narrow, coherent beam at something at 30 or 70 GHz.

Don't try to scare people away by bringing up terms which you don't understand. A microwatt is a lot of power at these frequencies.

Re:Good start, but let's rein in the enthusiasm a (1)

Muad'Dave (255648) | about 2 years ago | (#41022355)

Don't try to scare people away by bringing up terms which you don't understand. A microwatt is a lot of power at these frequencies.

I definitely understand the terms and agree that -42dBm is a useful amount of power at 60GHz. Thanks for the ad hominem.

My point is that if you've got all that power and all that real estate to run such a large and terribly inefficient signal source, what does using it actually give you?

In any real-world comms application I can think of (outside the laboratory), spatial and temporal coherence are not needed and introduce more problems that they solve. The beamwidth is narrow but is still diffraction-limited; the same limit can easily be achieved with normal high gain antennas (at 30-70GHz, high gain antennas are tiny).

If for some reason you need temporal coherence, your only choices of modulation are by direct modulation of the pump laser; that is, mixing (heterodyning) the output of the maser with a modulating signal by conventional means (semiconductor mixer, for instance) would destroy the coherence. I suppose you could do the mixing in a non-linear waveguide setup, but that would be a lot of microwave plumbing. Similar results can be achieved using regular old polarized antennas without limiting your modulation choices.

In other words, using a maser for comms is a solution looking for a problem.

In your example, a 1 watt optical laser would be at best 45% efficient [repairfaq.org] . So you're looking at about 2.2 Watts input for 63 uW out. A 20 GHz DRO [gedlm.com] followed by a doubler or tripler would give you significantly more output power per unit of input power, as well as be tunable and tiny. The DRO in the link consumes a maximum of 31.7 dBm of power and emits 13 dBm of RF. an IMPATT diode [insight-product.com] would be another good choice.

Re:Good start, but let's rein in the enthusiasm a (2)

necro81 (917438) | about 2 years ago | (#41012039)

Perhaps, but when the incoming microwave signal is measured in nanowatts or picowatts, a gain of 100 million is pretty damned awesome. Bulk electrical power is easy to come by; a stronger incoming signal is very hard to come by. Depending on the application, who cares if the efficiency of the equipment is lousy.

A better way to look at "efficiency" is to consider how much energy is required to transmit some unit of information across a certain distance. 1.5 kW electrical power is not actually all that much power for microwave transmission applications, especially if it means that the transmitter power can be turned down by, say, a factor of 10.

Re:Good start, but let's rein in the enthusiasm a (1)

Muad'Dave (255648) | about 2 years ago | (#41012719)

I should have quoted this part of the article: "When configured as an oscillator, the solid-state maser’s measured output power of around 10 decibel milliwatts is approximately 100 million times greater than that of an atomic hydrogen maser, which oscillates at a similar frequency (about 1.42 gigahertz)." [emphasis mine].

I was not referring to it's gain as an amplifier; rather it's rather meager output as a 1.42 GHz oscillator. For 1.5 kW in, I'd expect at least half that much power out to be considered useful at all (that's for a solid-state or tube oscillator).

Here's a tunable VCO [crystek.com] that uses 50mW to generate 2.5 mW from 1.277 to 1.691 GHz. That's 20:1.

The only use this thing has as an oscillator over other means are possibly frequency stability and coherence, neither of which are major concerns with regard to microwave transmission applications.

Re:Good start, but let's rein in the enthusiasm a (0)

Anonymous Coward | about 2 years ago | (#41013451)

The only use this thing has as an oscillator over other means are possibly frequency stability and coherence, neither of which are major concerns with regard to microwave transmission applications.

The efficiency is crap; certainly this maser is not a transmitter, unfortunately. A hugely powerful pencil thin coherent microwave beam is pretty interesting to think about.

Frequency stability is actually a major issue at higher microwave frequencies. Yes, a high quality crystal oscillator is pretty darn stable, but they are limited to fundamental resonances in low VHF; microwave frequencies require overtone oscillation or frequency multiplication, which both introduce noise and instability. This is obviously not a show stopper as we have been using microwave comms for half a century, but R&D is still ongoing.

A maser, on the other hand, can be used to build an atomic clock; it's stability at high frequencies really kicks the snot out of any XO. Even if it doesn't find common applications in the field, it will almost certain find applications in lab frequency references, GPS systems, satellites, etc.

Weak signal reception sounds like a huge potential application. This may obsolete the GaAsFET for weak signal amplification. Although being at room temperature, I doubt it could reach a 17k noise floor.

Re:Good start, but let's rein in the enthusiasm a (1)

sjames (1099) | about 2 years ago | (#41015535)

Considering that he got that first try with a far from perfect crystal he cooked up in a hurry, it's reasonable to expect some rapid improvements now that we know it''s not a complete waste of time.

Re:Good start, but let's rein in the enthusiasm a (1)

Muad'Dave (255648) | about 2 years ago | (#41022091)

I agree completely (that's why I said "Good start"), but the wild, rabid enthusiasm of other commenters need to take that into account. They obviously didn't RFTA, so they hear 'maser' and thought it meant 'death ray'.

PS - I think you may have made it onto the DEA's watch list with your phrase "crystal he cooked up in a hurry". :-)

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