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Bose-Einstein condensate created at room temperature
Vortex-L ^ | Feb 6 2013 | Axil Axil

Posted on 02/07/2013 12:43:29 PM PST by Kevmo

RE: [Vo]:Bose-Einstein condensate created at room temperature

Jones Beene Thu, 07 Feb 2013 11:13:22 -0800

Yes they can. In fact this could be important for LENR, should it be broad enough to include other boson quasiparticles, such as the magnon.

The definitions are similar: polaritons are quasiparticles resulting from strong coupling of electromagnetic waves with an electric or magnetic dipole-carrying excitation. The magnon could be imagined to be the subset of that - where the coupling is only magnetic. However, it may be only a partial subset with other features included.

Polaritons describe the dispersion of light (photons) with an interacting phonon resonance; while the magnon would describe the dispersion of spin current with an interacting resonance.

Using the same general terms, superconductivity where the Cooper pair is the boson, would describe the dispersion of charge within an interacting phonon resonance. (the last is my interpretation, which may not be correct).

Thus we have a linking of three BEC phenomena which may happen either at room temperature or close- in the case of the RTSC. From: Axil Axil

-------------------------------------------------------------

http://arstechnica.com/science/2013/02/bose-einstein-condensate-created-at-room-temperature/

Bose-Einstein condensate created at room temperature

-----------------------------------------

Can those interested in LENR draw any lessons from this formulation?

Cheers: Axil

--------------------------------------------------------------------------------------------------

Excerpt of Arstechnica article

Bose-Einstein condensate created at room temperature

Instead of atoms, condensation was achieved using quasiparticles.

by Matthew Francis- Feb 6 2013, 9:15am PST

Physical Sciences 27

Aluminum-Nitrogen nanowires, relatives of the ones used in these experiments.

NIH

Bose-Einstein condensation is a dramatic phenomenon in which many particles act as though they were a single entity. The first Bose-Einstein condensate produced in the laboratory used rubidium atoms at very cold temperatures—work that was awarded the 2001 Nobel Prize in physics. Other materials, like superconductors, exhibit similar behavior through particle interactions.

These systems typically require temperatures near absolute zero. But Ayan Das and colleagues have now used a nanoscale wire to produce an excitation known as a polariton. These polaritons formed a Bose-Einstein condensate at room temperature, potentially opening up a new avenue for studying systems that otherwise require expensive cooling and trapping.

Bosons are part of a large class of particles that can have the same quantum configuration or state. This is in contrast to the fermions, the category including electrons, protons, and neutrons, which resist having the same state. (This resistance, known as the Pauli exclusion principle, leads to the presence of different energy states, or orbitals, occupied by the electrons of atoms.) At extremely low temperatures, bosons can coalesce into a single quantum system known as a Bose-Einstein condensate (BEC), named for Satyendra Nath Bose and Albert Einstein.

Many atoms are bosons, though this characteristic doesn't generally make any difference except at high density or very low temperatures. However, thanks to the wonders of quantum physics, interactions within materials can produce quasiparticles. These are excitations that act like particles, but don't exist independent of the medium in which they occur.

As with normal particles, quasiparticles are either fermions or bosons, obeying the same general rules as their free cousins. For example, one widely accepted model for superconductivity describes the phenomenon as a Bose-Einstein condensation of quasiparticles formed by pairs of electrons. As with atomic BECs, quasiparticle BECs tend to form under very cold temperatures.

Another quasiparticle can be formed by the interactions between photons and excitations in a material. The resulting polaritons are low-mass bosons that should be able to condense at higher temperatures—possibly including room temperature. One signature of a polariton BEC is the production of coherent light—effectively, the quasiparticles act like a laser. Several experiments have created polariton BECs, though still at relatively cold temperatures.

The current study embedded a very thin wire—a nanowire—in a cavity designed to produce standing waves of microwave photons. The nanowire was an alloy of aluminum, gallium, and nitrogen, but with varying amounts of aluminum. The irregular composition created a de facto "trap" for the polaritons. A wire of uniform composition couldn't form a BEC—fluctuations within the material would destroy the condensation, even at low temperatures.

To bypass this, the researchers gradually decreased the amount of aluminum in the alloy to zero in the center of the nanowire, then bookended the aluminum-free segment with a region containing a relatively high amount of aluminum. The microwaves from the cavity interacted with the material, generating polaritons. These drifted preferentially along the wire toward the aluminum-free zone, where they collected and condensed.

In other words, the electronic properties of the material itself replaced the need for cooling, allowing the quasiparticles to gather and condense into a BEC. The experimenters confirmed this effect by detecting the telltale light emission.

This experiment marked the first room-temperature BEC ever observed in the laboratory. While the authors didn't suggest any practical application, the potential for studying BECs directly is obvious. Without the need for cryogenic temperatures or the sorts of optical and magnetic traps that accompany atomic BECs, many aspects of Bose-Einstein condensation can potentially be probed far less expensively than before.


TOPICS: Heated Discussion
KEYWORDS: canr; cmns; coldfusion; lenr; science
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Looks like Y.E. Kim's BEC theory for LENR just got a leg up. Criticisms of his theory were that BECs couldn't form at higher temperatures.

[PDF] Bose-Einstein Condensate Theory of Deuteron Fusion in Metal

http://www.physics.purdue.edu/people/faculty/yekim/YEKim-AIP-PNMBTG.pdf

File Format: PDF/Adobe Acrobat - Quick View by YE Kim - Cited by 14 - Related articles where ψBEC is the Bose-Einstein condensate ground state (a coherent quantum ..... Third International Conference on Cold Fusion., October 21-25 Nagoya ...

1 posted on 02/07/2013 12:43:37 PM PST by Kevmo
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To: dangerdoc; citizen; Liberty1970; Red Badger; Wonder Warthog; PA Engineer; glock rocks; free_life; ..

The Cold Fusion/LENR Ping List

http://www.freerepublic.com/tag/coldfusion/index?tab=articles


http://lenr-canr.org/


2 posted on 02/07/2013 12:45:36 PM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: Kevmo
For those threads when a pancake just won't do.

 

3 posted on 02/07/2013 12:46:53 PM PST by Responsibility2nd (NO LIBS. This Means Liberals and (L)libertarians! Same Thing. NO LIBS!!)
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To: Kevmo

This stuff interests me to no end. But I understand bupkis about the mechanics of it. I guess I will wait till it comes on the science channel so as to get the readers digest version.


4 posted on 02/07/2013 12:50:09 PM PST by Vaquero (Don't pick a fight with an old guy. If he is too old to fight, he'll just kill you.)
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To: Responsibility2nd

Thanks for bumping the thread

http://www.freerepublic.com/focus/f-chat/2965392/posts?page=19#19


5 posted on 02/07/2013 12:50:09 PM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: Responsibility2nd

Is that a waffle that was morphed via Higgs Bosuns from a pancake?

Cold waffle fusion with pure Vermont quantum syrup. YUM!


6 posted on 02/07/2013 12:53:28 PM PST by Vaquero (Don't pick a fight with an old guy. If he is too old to fight, he'll just kill you.)
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To: Vaquero

You might as well study the Nazi’s anti gravity flying saucers...or perhaps Charles Hapgood’s Hollow Earth Theory. All equally valid.


7 posted on 02/07/2013 12:57:53 PM PST by EEGator
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To: Responsibility2nd
For threads like this I prefer:
8 posted on 02/07/2013 1:00:33 PM PST by Abathar (Proudly posting without reading the article carefully since 2004)
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To: Kevmo

I may be looking right at it and missing it. Is there a link to the actual presentation of this paper? Utterly fascinating. Thanks for posting. The effect on super conductors alone will be astounding.


9 posted on 02/07/2013 1:00:33 PM PST by RIghtwardHo
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To: Vaquero
Is that a waffle that was morphed via Higgs Bosuns from a pancake? Cold waffle fusion with pure Vermont quantum syrup. YUM!

Waffles and syrup would be more likely to generate free energy.
10 posted on 02/07/2013 1:01:45 PM PST by ZX12R
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To: EEGator

The NAZIs did have a flying saucer program, not based upon antigravity but straightforward boundary layer control as laid down by Prandtl in the 1920’s. The allies won the war & got all their secrets.

Why would $multibillion companies like Mitsubishi, STMicro, Toyota, and National Instruments stick their necks out for something like the hollow earth theory?


11 posted on 02/07/2013 1:04:42 PM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: RIghtwardHo
http://www.pnas.org/content/early/2013/01/29/1210842110 Polariton Bose–Einstein condensate at room temperature in an Al(Ga)N nanowire–dielectric microcavity with a spatial potential trap Ayan Dasa,1, Pallab Bhattacharyaa,1, Junseok Heoa, Animesh Banerjeea, and Wei Guob Author Affiliations Edited by Paul L. McEuen, Cornell University, Ithaca, NY, and approved December 21, 2012 (received for review June 28, 2012) Abstract A spatial potential trap is formed in a 6.0-μm Al(Ga)N nanowire by varying the Al composition along its length during epitaxial growth. The polariton emission characteristics of a dielectric microcavity with the single nanowire embedded in-plane have been studied at room temperature. Excitation is provided at the Al(Ga)N end of the nanowire, and polariton emission is observed from the lowest bandgap GaN region within the potential trap. Comparison of the results with those measured in an identical microcavity with a uniform GaN nanowire and having an identical exciton–photon detuning suggests evaporative cooling of the polaritons as they are transported into the trap in the Al(Ga)N nanowire. Measurement of the spectral characteristics of the polariton emission, their momentum distribution, first-order spatial coherence, and time-resolved measurements of polariton cooling provides strong evidence of the formation of a near-equilibrium Bose–Einstein condensate in the GaN region of the nanowire at room temperature. In contrast, the condensate formed in the uniform GaN nanowire–dielectric microcavity without the spatial potential trap is only in self-equilibrium. Bose–Einstein condensation exciton–polariton Footnotes 1To whom correspondence may be addressed. E-mail: ayandas@umich.edu or pkb@umich.edu. Author contributions: A.D. and P.B. designed research; A.D. and J.H. performed research; J.H., A.B., and W.G. contributed new reagents/analytic tools; A.D. analyzed data; and P.B. wrote the paper. The authors declare no conflict of interest. This article is a PNAS Direct Submission. This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1210842110/-/DCSupplemental. Freely available online through the PNAS open access option.
12 posted on 02/07/2013 1:07:20 PM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: Kevmo
In fact this could be important for LENR,

Most likely, nothing scientifically legitimate has anything to do with LENR or cold fusion.

13 posted on 02/07/2013 1:11:03 PM PST by Moonman62 (The US has become a government with a country, rather than a country with a government.)
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To: RIghtwardHo
hopefully better formatting

http://www.pnas.org/content/early/2013/01/29/1210842110

Polariton Bose–Einstein condensate at room temperature in an Al(Ga)N nanowire–dielectric microcavity with a spatial potential trap

Ayan Dasa,1,
Pallab Bhattacharyaa,1,
Junseok Heoa,
Animesh Banerjeea, and
Wei Guob

Author Affiliations

Edited by Paul L. McEuen, Cornell University, Ithaca, NY, and approved December 21, 2012 (received for review June 28, 2012)

Abstract

A spatial potential trap is formed in a 6.0-μm Al(Ga)N nanowire by varying the Al composition along its length during epitaxial growth. The polariton emission characteristics of a dielectric microcavity with the single nanowire embedded in-plane have been studied at room temperature. Excitation is provided at the Al(Ga)N end of the nanowire, and polariton emission is observed from the lowest bandgap GaN region within the potential trap. Comparison of the results with those measured in an identical microcavity with a uniform GaN nanowire and having an identical exciton–photon detuning suggests evaporative cooling of the polaritons as they are transported into the trap in the Al(Ga)N nanowire. Measurement of the spectral characteristics of the polariton emission, their momentum distribution, first-order spatial coherence, and time-resolved measurements of polariton cooling provides strong evidence of the formation of a near-equilibrium Bose–Einstein condensate in the GaN region of the nanowire at room temperature. In contrast, the condensate formed in the uniform GaN nanowire–dielectric microcavity without the spatial potential trap is only in self-equilibrium.

Bose–Einstein condensation
exciton–polariton
Footnotes
1To whom correspondence may be addressed.
E-mail: ayandas@umich.edu or pkb@umich.edu.



Author contributions: A.D. and P.B. designed research; A.D. and J.H. performed research; J.H., A.B., and W.G. contributed new reagents/analytic tools; A.D. analyzed data; and P.B. wrote the paper.

The authors declare no conflict of interest.

This article is a PNAS Direct Submission.

This article contains supporting information online at
http://www.pnas.org/lookup/suppl/doi:10.1073/pnas.1210842110/-/DCSupplemental.

Freely available online through the PNAS open access option.
14 posted on 02/07/2013 1:11:59 PM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: Moonman62; ZX12R

Thanks for bumping the thread

http://www.freerepublic.com/focus/f-chat/2965392/posts?page=19#19


15 posted on 02/07/2013 1:13:26 PM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: Kevmo
File Format: PDF/Adobe Acrobat - Quick View by YE Kim - Cited by 14 - Related articles where ψBEC is the Bose-Einstein condensate ground state (a coherent quantum ..... Third International Conference on Cold Fusion., October 21-25 Nagoya ...

That conference was held in 1992 back when cold fusion was like the real estate boom of the 2000's.

16 posted on 02/07/2013 1:15:27 PM PST by Moonman62 (The US has become a government with a country, rather than a country with a government.)
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To: Kevmo
Thanks for bumping the thread

Put me on your ping list so I can bump it sooner.

17 posted on 02/07/2013 1:17:00 PM PST by Moonman62 (The US has become a government with a country, rather than a country with a government.)
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To: Moonman62

Again, no. Your stalking works. You bump these threads faster and more frequently than 90% of those on the LENR ping list. Not that what you say is worth reading, but at least you bump the thread.


18 posted on 02/07/2013 1:23:06 PM PST by Kevmo ("A person's a person, no matter how small" ~Horton Hears a Who)
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To: Vaquero
It's actually very simple. Quantum systems involve "entanglement" of the wave functions of the particles involved. [Unlike Classical Physics, where the location of the particles alone specifies that they are distinct.] In quantum systems, if you have two particles, you never really have two distinct particles. You always have a system composed of two particles; there is no way to tell which one is which.

It's like having identical twins with absolutely no differences, and they themselves do not even know who is who(m). When you combine the wave functions of those two particles, they can be either symmetric or antisymmetric when the positions of the two particles trade places.

Particles that pair in systems that give rise to antisymmetric wave functions are called fermions. Particles that pair in systems that give rise to symmetric wave functions are called bosons.

Systems made up of very large numbers of fermions must essentially have one energy level for each particle in the system (this is not exactly true -- there is a complication but it doesn't change things much conceptually, so read on.) Systems made up of very large numbers of bosons do not need to have more than a single energy level for ALL of them (they usually do, but they don't HAVE TO.)

At all but VERY LOW temperatures, there are many energy levels available, so systems composed of many fermions at high temperature look just like systems composed of many bosons at high temperature. But, as the temperature falls, there is less and less energy available (that is actually nothing more than the microscopic definition of temperature.) This means there are fewer and fewer energy levels to occupy. For bosons, this is not a problem, because all of the bosons can occupy the same energy level if they have to. However, with fermions, each fermion must have its own energy level, so no matter how low the temperature goes, there are fermions "locked" into higher energy states.

Think of fermions like this: your kids are not grown up, and they get to bickering in the back seat when they touch each other (Dad! He's touching me!) You may have a van with three rows of seats that theoretically holds nine kids, but because of the Notouchy Effect (Pauli Exclusion Principle) the kids must each have their own row of seats, so your car can hold no more than three kids, if your kids are fermions.

On the other hand, the Brady Bunch kids are all perfect and love each other and are willing to sit in each others' laps if necessary. You can fit all six Brady kids all into the same row. Those are bosons.

Because systems with large numbers of fermions must fill large numbers of quantum levels, even at low temperature, they behave much differently than systems of bosons, all of which are willing to fit into the lowest available state.

[Now there is one very slight omission I promised to get back to: two fermions with the same "spin" quantum number are not actually in the same state even if they have the same energy. Quantum spin for fermions can have one of only two possible states. So in fact, each energy level for fermions can contain two, not just one particle(s). The idea is still the same.]

19 posted on 02/07/2013 1:24:07 PM PST by FredZarguna (Use it as you will. I Could NOT care less.)
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To: Kevmo

I was referring specifically to the anti gravity “zero-point energy” based power systems. I figured you’ve probably seen videos online.(conspiracy theory explanations)

You seem like a smart guy, I don’t know why you waste your scientific inquisitiveness on cold fusion, LENR, and specifically Rossi.


20 posted on 02/07/2013 1:28:29 PM PST by EEGator
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