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German Scientists Create Bose-Einstein Condensate Using Photons

Soulskill posted more than 3 years ago | from the keep-this-discovery-away-from-sharks dept.

Science 61

xt writes "A team of physicists, led by the University of Bonn's Martin Weitz, have managed to create a Bose-Einstein condensate (here's a more detailed explanation) out of photons, previously thought to be impossible. The research was published in the journal Nature (abstract, and the arXiv has the submitted paper as a PDF) and has possible applications on solar energy technology and shortwave lasers, which would be well-suited to the manufacture of computer chips as the process uses lasers to etch logic circuits onto semiconductor materials. Seems like Moore's law is safe again!"

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61 comments

F1RST P0ST! (0)

woolio (927141) | more than 3 years ago | (#34353248)

How do you like them photons?

Re:F1RST P0ST! (0)

rudy_wayne (414635) | more than 3 years ago | (#34353324)

Einstein is responsible for those crappy Bose speakers?

Re:F1RST P0ST! (2, Funny)

Brad1138 (590148) | more than 3 years ago | (#34353372)

You know it isn't nice to insult crap like that.

Re:F1RST P0ST! (0, Offtopic)

hosecoat (877680) | more than 3 years ago | (#34353516)

Rubidium is the best element name i've ever heard

Re:F1RST P0ST! (0, Offtopic)

Anonymous Coward | more than 3 years ago | (#34353782)

Better than krypton, xenon, titanium, technecium, or unununium (sounds like a Phil Collins paradody)?

Click 3 Times (1)

sanman2 (928866) | more than 3 years ago | (#34353784)

Click your heels 3 times, and say:

There's no laze like Bose!
There's no laze like Bose!
There's no laze like Bose!

Re:F1RST P0ST! (2, Interesting)

Monkeedude1212 (1560403) | more than 3 years ago | (#34354160)

You know whats odd?

If this was previously thought to be impossible - you'd think it would have much larger implications.

Perhaps they should have said previously thought to be improbable?

Re:F1RST P0ST! (1)

infaustus (936456) | more than 3 years ago | (#34363086)

I think this was pretty firmly considered impossible - there is a problem in my stat mech textbook (Kittel and Kromer, Thermal Physics) as follows: 7.7) Photon condensation. Consider a science fiction universe in which the number of photons N is constant, at a concentration of 10^20 cm^-3. The number of thermally excited photons we assume is given by the result of Problem 4.1, which is Ne=2.404V(tau^3)/(pi^2hbar^3c^3). Find the critical temperature in K below which Ne N. The excess N - Ne will be in the photon mode of lowest frequency; the excess might be described as a photon condensate in which there is a large concentration of photons in the lowest mode. In reality there is no such principle that the total number of photons be constant, hence there is no photon condensate.

physics marketing (3, Funny)

girlintraining (1395911) | more than 3 years ago | (#34353382)

Super Photons, original flavor: Not From Condensate.
Regular Photons: From Condensate.
Spooky Photons: (Note: contains only about 50% of stated volume)

Moore's law is worthless right now... (2, Insightful)

wealthychef (584778) | more than 3 years ago | (#34353386)

"Seems like Moore's law is safe again!"

That's great, but if memory and I/O speeds don't keep up, the extra FLOPS are becoming more and more worthless....

Re:Moore's law is worthless right now... (1)

Baseclass (785652) | more than 3 years ago | (#34353394)

One less bottleneck is always a good thing in my book.

Re:Moore's law is worthless right now... (1)

wealthychef (584778) | more than 3 years ago | (#34353550)

True, but FLOPS have not been the bottleneck for a long time. When was the last time you had to up your CPU speed or used all your CPU? But people always need RAM and disk I/O to be faster. This gets worse every year. At giant supercomputing facilities, this is well known. I wonder when it will start hitting the consumer level?

Re:Moore's law is worthless right now... (3, Interesting)

Anonymous Coward | more than 3 years ago | (#34353638)

True, but FLOPS have not been the bottleneck for a long time. When was the last time you had to up your CPU speed or used all your CPU?

Last night. Then again, I was trying to play a game on netbook, so I had it coming. Really, for a desktop, if I am not getting enough speed I am probably just being cheap and not upgrading, but for a netbook or phone, a faster processor would make a noticeable performance difference. I agree that the other stuff is important too, but CPUs are still a bottleneck for real consumer applications, just not on the desktop.

Re:Moore's law is worthless right now... (1)

wealthychef (584778) | more than 3 years ago | (#34374370)

Hmm, when you say you were maxed out on CPU with a game -- did you mean that your graphics card was maxed out? Are games really that CPU intensive? But it's a fair point, that increasing FLOPS/Watt is an advantage for small portable devices. I am guessing that your GPU (not CPU) was maxed out and that more memory in your GPU would make a big difference.

Re:Moore's law is worthless right now... (1)

ClintJCL (264898) | more than 3 years ago | (#34353704)

Firefox maxes one core out all the time. I could certainly use more flops.

Re:Moore's law is worthless right now... (2, Informative)

camperdave (969942) | more than 3 years ago | (#34354118)

Firefox maxes one core out all the time. I could certainly use more flops.

No, you could use a better version of Firefox. There's no reason a browser should max out a current multi-core CPU.

Re:Moore's law is worthless right now... (0, Troll)

ClintJCL (264898) | more than 3 years ago | (#34354176)

Because of course you know everything about every computer and every situation. Haha. Hilarious "generic defensive geek" archtype response.

Re:Moore's law is worthless right now... (1)

wealthychef (584778) | more than 3 years ago | (#34354686)

Well, actually there are two possibilities; either you have a single-core machine, in which case the current conversation doesn't really apply to you as you are not taking advantage Moore's law anyhow, or Firefox is not making use of all that horsepower. Put good software on a good machine and what will limit it is memory and/or I/O, if anything.

Re:Moore's law is worthless right now... (1)

ClintJCL (264898) | more than 3 years ago | (#34355096)

Firefox only uses one core. Moore's law still applies, however. The rate of cores becoming faster, y'know. Not using a 2nd core doesn't just throw all that out the window. Slapping on a second core doesn't make things twice as fast, either. Very few things use both cores. (I'm on a 32 bit operating system.) One notable one is LAME encoder.

Point being - under the same conditions [firefox using 1 of 2 cores], a faster cpu will use faster cores and will result in this happening less often.

I do find your response infinitely smarter than the other response to my comment though :)

Re:Moore's law is worthless right now... (0)

Anonymous Coward | more than 3 years ago | (#34357920)

Exactly what strange variant of Moore's law are you going by?

Moore's law states that the number of transistors that can be placed inexpensively on an integrated circuit has doubled approximately every two years.

If you aren't taking advantage of using all the circuits you could, Moore's law doesn't apply. No where in Moore's law does it state each core would get faster, or each pipeline would get faster, or any other subcomponent of a CPU. Just that the number of transistors would double. No one said the transistors had to be part of the same core.

Re:Moore's law is worthless right now... (1)

ClintJCL (264898) | more than 3 years ago | (#34358860)

Did anyone say that they couldn't be?

Re:Moore's law is worthless right now... (1)

maxwell demon (590494) | more than 3 years ago | (#34360156)

You know, there's something called JavaScript.

Re:Moore's law is worthless right now... (1)

maxwell demon (590494) | more than 3 years ago | (#34360150)

Only if you open Slashdot with a long discussion. Really, it's the only page I'm visiting regularly which maxes one core out for an extended time.
Well, at least now it's fast enough that I don't get a browser warning that a script takes too long (there was a time where Slashdot triggered that regularly).

Re:Moore's law is worthless right now... (1)

ClintJCL (264898) | more than 3 years ago | (#34360172)

"Slashdot: Most CPU intensive page in existence."

Augh (0)

Anonymous Coward | more than 3 years ago | (#34353530)

Stop using FLOPS as a benchmark!

Re:Moore's law is worthless right now... (0)

Anonymous Coward | more than 3 years ago | (#34354030)

can't we design mechanical loops of machine instructions below the memory access time producing random data that is prematurely designed to encompass more information? kinda like the demo scene does it? (more noise than signal, but still more signal than in the instructions themselves, this signal being produced through the loop). esoteric, yes - but useful, maybe.

Re:Moore's law is worthless right now... (1)

FatdogHaiku (978357) | more than 3 years ago | (#34354344)

"Seems like Moore's law is safe again!"

That's great, but if memory and I/O speeds don't keep up, the extra FLOPS are becoming more and more worthless....

Well, THAT'S why it's so important to do things that were previously thought to be impossible.
Once we finally get small scale time travel going we can write memory values before the calculation is actually performed!
Slow I/O? No problem as the information arrives before it is sent... so it's always on time for the super fast processor to make the next calculation and send the result back in time to the slower I/O and memory!
I don't know why but I get this vision of a heat sink that looks like a 12 acre lake...

Re:Moore's law is worthless right now... (1)

Theovon (109752) | more than 3 years ago | (#34358548)

Our CS department chair made an interesting comment the other day (although I think he was quoting someone else). When it comes to energy consumption in todays processors, computation is almost free. All the energy goes into moving data around.

As for memory... (1)

tygerstripes (832644) | more than 3 years ago | (#34373328)

Wouldn't an improved (shrunk) fab process also be used to improve memory and storage (SSD) performance? It really is all about the I/O now.

lithography applications (1)

kyle5t (1479639) | more than 3 years ago | (#34353440)

So this would presumably be used for extreme ultraviolet lithography [wikipedia.org] ?

I guess this paragraph from the Wikipedia article may be relevant:

A further characteristic of the plasma-based EUV sources under development is that they are not even partially coherent, unlike the KrF and ArF excimer lasers used for current optical lithography. Further power reduction (energy loss) is expected in converting incoherent sources (emitting in all possible directions at many independent wavelengths) to partially coherent (emitting in a limited range of directions within a narrow band of wavelengths) sources by filtering (unwanted wavelengths and directions). On the other hand, coherent light poses a risk of monochromatic reflection interference and mismatch of multilayer reflectance bandwidth.

Idea (1)

durrr (1316311) | more than 3 years ago | (#34353486)

As the photon BEC works at room temperature and seems quite simple, and shows a switching behaviour, can't it simply be miniaturized and used as a replacement of circuitry instead of used for lithography?

Re:Idea (2, Insightful)

dpilot (134227) | more than 3 years ago | (#34353644)

Better yet, if it really works at room temperature, this method will still be workable once we've squandered the world's supply of helium. (Thanks for a "free market" solution, Congress.)

How much other basic science is going to shortly become impossible - basically prohibitively expensive when we hit the end of "Cheap Helium"?
Makes you wonder what fraction of helium is in the parade floats, and if they attempt to scavenge any of it.

Re:Idea (1)

John Hasler (414242) | more than 3 years ago | (#34355038)

> Thanks for a "free market" solution, Congress.

There's nothing "free market" about depressing the price by an order of magnitude or so by dumping stockpiles.

Re:Idea (1)

dpilot (134227) | more than 3 years ago | (#34355592)

That was kind of my point, but I'll bet at the time it was heralded as a "market-oriented bipartisan solution." At the time, it rather slipped under my radar screen - I didn't hear about the mess until about 6 months ago.

Re:Idea (2, Informative)

Anonymous Coward | more than 3 years ago | (#34353760)

As the photon BEC works at room temperature and seems quite simple, [...] can't it simply be miniaturized and used as a replacement of circuitry instead of used for lithography?

Define simple.

You do realise how good the technology you want to replace really has become?
MOSFET's are reliable switches that are really, really small.

They are so small, modern transistors are composed of a number of atoms that
humans can actually imagine.

There are few other technological items that are that small, and yet fullfil a
task with incredible reliability over a long period of time as an individual device.
I actually don't know of any right now.

If you can't miniaturize these cavities to sub micrometer dimensions, they would
have to be _incredibly_ fast switches to compensate for a sheer lack of number.

The sales pitch is unnecessary (3, Insightful)

Interoperable (1651953) | more than 3 years ago | (#34353512)

The research is a fascinating work about fundamental physics. This is one case where a sales pitch about about possible, only tangentially related applications in computing is quite unnecessary.

Re:The sales pitch is unnecessary (1)

fraktalek (1871686) | more than 3 years ago | (#34353834)

But in this case it's interesting and informative nevertheless. At least for me.

What exactly is this? (1)

pclminion (145572) | more than 3 years ago | (#34353600)

How is a Bose-Einstein condensate of photons any different than regular ol' standing wave?

Who Cares? Weaponize It! (1)

sanman2 (928866) | more than 3 years ago | (#34353882)

Photons bouncing around inside the resonant cavity could be considered a standing wave, but the BEC requires them to reach a minimum critical density in order to achieve the BEC state. Meanwhile lasers formed by traditional population inversion can happen at any amplitude.

Re:What exactly is this? (2, Informative)

Interoperable (1651953) | more than 3 years ago | (#34355368)

It's a pretty dense article but, as far as I can tell, they're considering the motion of the photons in the plane transverse to the cavity axis as the particle movement. The problem is then two-dimensional in nature with the curvature of the mirrors directing photons back towards the cavity center. The situation is then analogous to a two-dimensional gas of particles confined by a central trapping potential.

In essence, the temperature is related to the transverse velocity of the intra-cavity photons. I believe that the cavity is spatially multi-mode and the quantum state of a photons is which spatial mode it's in and how it's evolving. Interaction with the dye particles randomizes (thermalizes) the quantum state of each photon, resulting in each photon engaging in a thermal random walk about the cavity's transverse modes. They then found the critical parameters for the "photon gas" to condense into occupying the lowest energy state (probably the fundamental Gaussian cavity mode).

Again, it's a pretty strange paper so I may have some details wrong. Fundamentally though, it's about modelling the transverse motion of photons in a cavity as particle motion, introducing thermal noise through scattering, then analyzing the dynamics by comparing to atomic motion and showing similar condensation at appropriate parameters. Quite an amazing paper.

Re:What exactly is this? (1)

tygerstripes (832644) | more than 3 years ago | (#34373338)

What?

I'll believe this is relevant once... (0)

Anonymous Coward | more than 3 years ago | (#34353736)

It shows up on the Big Bang Theory.

Otherwise it's not important.

Wait - the Germans have access to Science again? (1, Funny)

Rogerborg (306625) | more than 3 years ago | (#34353774)

Then God help us. God help us all.

Re:Wait - the Germans have access to Science again (1)

martin-boundary (547041) | more than 3 years ago | (#34354036)

British subject, do not worry if we all die, for the Lord knows them that are His!

No! They're Our Friends Now! (1)

Greyfox (87712) | more than 3 years ago | (#34354840)

To Quote Tom Leher:

Once all the Germans were warlike, and mean
But that couldn't happen again!
We taught them a lesson in 1918
And they've hardly bothered us since then!

Re:Wait - the Germans have access to Science again (-1, Flamebait)

PolygamousRanchKid (1290638) | more than 3 years ago | (#34356176)

I work in Germany, and was on a business trip to the US. One of my colleagues from the US asked me, "Germany? What do they produce, what industry do they have?" I answered, "Um, among other things, they manufacture cars." The discourse continued:

"What cars? What cars are made in Germany!"

"Um, like, BMW and Mercedes."

"Really? They are made in Germany?"

So Germany is using science now to produce better cars.

I saw a documentary about "innovations" in weapons. Those nasty Nazi folks invented the cruise missile. They called it the V-1. They also had plans to drop a "dirty bomb" on New York City. (Not that anyone in NYC would have noticed.)

As a pinnacle of engineering, the German rail service is planning a dubious undertaking of a major reconstruction of the main train station in the city of Stuttgart. Since the normal local folks raised cain about it, there are now open hearings to discuss this. If you can understand German, this is a hoot and a half to watch. The guy from the train service has a "shit-eating grin." Accountants from PriceWaterhouseCoopers said that, "Well, the project might be around 1 billion € underestimated."

The rail service guy drew some diagrams, and tried to explain some mathematics which were above all of the politicians' heads, with diameter of the tunnel, and pi, and price per meter of tunnel.

One of the opponents asked, "I don't want to know what the price is, per tunnel meter. What will the damn thing cost, in the end?"

Wait - the morons have access to Slashdot again? (1, Insightful)

Anonymous Coward | more than 3 years ago | (#34356850)

Then God help us. God help us a- anyway, I'm not religious.

In Between (1)

camperdave (969942) | more than 3 years ago | (#34354284)

The first link [wikipedia.org] reads like an elementary school primer, while the second link [wikipedia.org] reads like a PHD dissertation. Is it not possible to explain quantum mechanics at a normal adult level?

Re:In Between (0)

Anonymous Coward | more than 3 years ago | (#34354512)

The first one is from simple.wikipedia.org. Have you tried this one yet? en.wikipedia.org/wiki/Bose-Einstein_condensation

Re:In Between (2, Insightful)

Anonymous Coward | more than 3 years ago | (#34354570)

no. you either get dumbed down, or you get equations.

shit's complicated. deal with it or deal with not understanding it.

Re:In Between (1)

hweimer (709734) | more than 3 years ago | (#34355516)

The first link [wikipedia.org] reads like an elementary school primer, while the second link [wikipedia.org] reads like a PHD dissertation. Is it not possible to explain quantum mechanics at a normal adult level?

Lemme try:

Quantum mechanics tells us that there are only discrete energy levels allowed within any physical system. For example, if you put a single particle into a box, the allowed energy levels a given by plane (matter) waves. Now, you don't have only a single particle, but say a million of them. Since they are the same atoms, they are indistinguishable. So, you cannot say that atom A is in level X and atom B is in level Y, but only that 2 atoms are in level X and 5 atoms are in level Y and so on. Since we are dealing with bosons, we may just put all atoms into the same energy level to find the configuration with minimum energy for the entire system. For our plane waves, this energy level would correspond to a simple half-cycle of a cosine, if we set the boundaries of the box to be at x=(+/-)pi/2.

Okay, so now we now what the minimum energy configuration is. But such a state would only be reached at absolute zero temperature, which is impossible to achieve. So what happens at finite temperatures? On first thought one would think that thermal fluctuations would lead to a population of the other energy levels, with temperature roughly indicating how far up in energy we will go. Since there a gazillion of energy levels in a macroscopic system, one would expect that the probability to find the system actually in the minimum energy level to be essentially zero.

But this is not true for very low temperatures. One can show that such a configuration can only accompany a finite number of bosons. If we put more bosons than this number into our box, they will happily pile up in the level of minimum energy and its probability will shoot through the roof. This is when we have created a Bose-Einstein condensate.

Re:In Between (1)

camperdave (969942) | more than 3 years ago | (#34356330)

Does this work?

Any elementary particle, atom, or molecule, can be classified as one of two types: a boson or a fermion. For example, an electron is a Fermion, while a photon or a helium atom is a Boson.

Fermions can be elementary, like the electron, or composite, like the proton. All observed fermions have half-integer spin. An important characteristic of a Fermion is that it obeys the Pauli exclusion principle. Thus, if more than one fermion occupies the same place in space, the properties of each fermion (e.g. its spin, or energy) must be different from the rest. Similarly, Bosons may be either elementary, like photons, or composite, like mesons. unlike Fermions, Bosons do not obey the Pauli exclusion principle, and any number can exist in the same place and quantum state.

Normally, when a gas consisting of bosons is chilled, the quantum states of the bosons is random. The gas behaves as an ideal gas. However, at temperatures near absolute zero, the bosons start to occupy only the lowest quantum energy states, and a Bose-Einstein condensate forms. In this state, quantum effects on the atomic scale begin to appear on a macroscopic scale. An example is superfluidity.

The New Monster? (2, Funny)

Michael_Burton (608237) | more than 3 years ago | (#34354488)

What I want to know is: Will this do as much to improve the sound of my Bose speakers as Monster cables do?

Re:The New Monster? (-1)

Anonymous Coward | more than 3 years ago | (#34355070)

Yes.

So? (0)

Anonymous Coward | more than 3 years ago | (#34354640)

1. You can create a BEC from matter.
2. Matter is _MADE_ out of photons. (matter + anti-matter = photons; thus photons are the real elementary particles of all matter)
3. You can create matter from photons (pair-production and the Big Bang)

Thus...

4. Photons -> Matter -> BEC (synchronized particles)

No, the cat does not, in fact, "got my tongue." (1)

Impy the Impiuos Imp (442658) | more than 3 years ago | (#34355210)

Neither the linked wiki to the layman's explanation, nor the "detailed" one explain it the way I think I understand it.

As you cannot know momentum and position simultaneously with great accuracy (I think it's those two anyway), when you cool these down to near absolute zero, you know their momentum very accurately, which is almost zero. Hence their positional accuracy skyrockets into fuzziness.

Can someone please clean this up for me so I can understand it better?

Re:No, the cat does not, in fact, "got my tongue." (1)

nashv (1479253) | more than 3 years ago | (#34362190)

Heisenberg's Uncertainty principle : For a particle, the mutiplication of a change in momentum (x) and position(y) is a constant. (roughly speaking).

Which means that if x is close to zero, and there is only infinitessimaly small change in x, the change in y (position) is infinitesimally large, which means you have no freakin idea where it is at any given moment of time.

thats the best I can do

Implications... (1)

Genda (560240) | more than 3 years ago | (#34356528)

Tell me this won't lead to sentences like "Excuse me, but could I please borrow a cup of red light???"

Re:Implications... (1)

Walt Dismal (534799) | more than 3 years ago | (#34356614)

My name is Arnold Rimmer, and I can tell you I have been waiting for a hard light drive for simply eons. As soon as I get one, I shall lend the requested cup of red light, but you must furnish me with a 27b/6 form first.

yeah sure but (1)

mgabrys_sf (951552) | more than 3 years ago | (#34361220)

How does it taste?

Not so funny (1)

nashv (1479253) | more than 3 years ago | (#34362166)

It saddens me to see all these oh-so-funny Bose audio system jokes. Its rather an injustice to the scientific work of Satyendra Bose [wikipedia.org] .
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