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ppyadof
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What exactly does a Bose-Einstein Condensate look like with the naked eye? Is there any special about what it looks like through the optical part of the spectrum? What are the electromagnetic properties of a BEC as a whole?
If you mean a literal bowl the condensate shouldn't survive for long. Making solids that cold is impossible afaik.Niles said:I read that if the condensate is placed in e.g. bowl,[...]
Cthugha said:..., I am still not really convinced. For example there was still no conclusive and quantitative measurement on the intensity correlation, which would clearly demonstrate a spontaneous phase transition.
Creator said:Cthugha; I haven't kept up with solid state bec's ...but..
Would this mean that there is no BEC in the cavity or that it simply is not lasing.??
Cthugha said:I don't know, whether I got your question right.
Niles said:I read that if the condensate is placed in e.g. bowl, then some of the condensate will actually try and escape outside the bowl, because the potential is lower outside the bowl. So the BEC will look like a sine wave just as we know it from the potential well in quantum mechanics,
Creator said:Ok, so condensation is equivalent to polariton lasing, (but similar to 'single pass' lasing), no?
Creator said:So empirically, if the detected photon is characterictic of the polariton BEC, and is distinquishable from photonic lasing, why the ambiguity ? Is bunching the only signature? or is there a polarization condition?
Cthugha said:Yes, that is the major opinion and I think so, too. Polariton lasing is supposed to work due to bosonic final state stimulation and is equal to condensation.
Well, the main problem is the question, where the coherence comes from. There ae three main ways to get the condensate: nonresonant excitation, resonant excitation at k=0 or stimulated scattering by resonant excitation near the magic angle, which starts an OPO-like process. ...
Creator said:1. what is the polariton spin state at k=0.
Creator said:2. Pragamatically; Have there been any temperature measurements to empirically establish a critical temperature (of phase transition) above which apparent condensation effects disappear...{since low effective polariton mass ( in the range of photon eff. mass) seems to make it canidiate for high temp. condensate of high efficiency?}
A BEC, or Bose-Einstein Condensate, is a state of matter where a group of atoms behave as a single entity, exhibiting quantum mechanical properties on a macroscopic scale. This state can only be achieved at extremely low temperatures, close to absolute zero.
A BEC is created by cooling a gas of atoms to near absolute zero using specialized equipment such as lasers and magnetic fields. This allows the atoms to lose their individual identities and merge into a single quantum state.
A BEC appears as a cloudy, dense gas due to the superposition of all the atoms in the same quantum state. At higher temperatures, the gas would appear as a diffuse cloud, but at the extremely low temperatures required for a BEC, the atoms are tightly packed together.
BECs have many potential applications in fields such as quantum computing, precision measurements, and atomic clocks. They can also be used to study fundamental quantum phenomena and simulate other complex systems.
A BEC is fundamentally different from other states of matter, such as solids, liquids, and gases, because it is a quantum state rather than a classical one. This means that the atoms in a BEC behave as waves rather than particles, and they all exist in the same quantum state instead of having individual identities.