https://arxiv.org/pdf/1411.6822
Exciton-polariton condensates
Tim Byrnes,1 Na Young Kim,2 and Yoshihisa Yamamoto1, 2
1National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo
101-8430, Japan
2E. L. Ginzton Laboratory, Stanford University, Stanford, CA 94305
(Dated: November 26, 2014)
Recently a new type of system exhibiting spontaneous coherence has emerged
{ the excitonpolariton
condensate. Exciton-polaritons (or polaritons for short) are bosonic
quasiparticles that
exist inside semiconductor microcavities, consisting of a superposition of
an exciton and a cavity
photon. Above a threshold density the polaritons macroscopically occupy the
same quantum state,
forming a condensate. The lifetime of the polaritons are typically
comparable to or shorter than
thermalization times, making them possess an inherently non-equilibrium
nature. Nevertheless,
they display many of the features that would be expected of equilibrium
Bose-Einstein condensates
(BECs). The non-equilibrium nature of the system raises fundamental
questions of what it means
for a system to be a BEC, and introduces new physics beyond that seen in
other macroscopically
coherent systems. In this review we focus upon several physical phenomena
exhibited by excitonpolariton
condensates. In particular we examine topics such as the di erence between
a polariton
BEC, a polariton laser, and a photon laser, as well as physical phenomena
such as super
uidity,
vortex formation, BKT (Berezinskii-Kosterlitz-Thouless) and BCS
(Bardeen-Cooper-Schrie er)
physics. We also discuss the physics and applications of engineered
polariton structures.
On Wed, Jul 19, 2017 at 3:04 AM, Che <comandantegri...@gmail.com> wrote:
>
>
> On Wed, Jul 19, 2017 at 3:02 AM, Axil Axil <janap...@gmail.com> wrote:
>
>> I'm no fyzicist, but BECs are the quantum state of matter absolutely
>> requiring the least possible amount of energy in the system as is possible
>>
>> This is not an absolute. When polaritons are confined in an optical
>> cavity over time, FANO interference forces the waveform into a soliton. In
>> other words, long term confinement of EMF leads to the formation of a BEC
>> through interference.
>>
>
> I did not know that. But this is only a _virtual_ BEC, no..?
>
>
>
>
>
>
>
>
>>
>> On Wed, Jul 19, 2017 at 2:56 AM, Che <comandantegri...@gmail.com> wrote:
>>
>>>
>>>
>>> On Wed, Jul 19, 2017 at 2:35 AM, Kevin O'Malley <kevmol...@gmail.com>
>>> wrote:
>>>
>>>> Wouldn't that be fascinating if High Temp Superconductors were
>>>> generating linear BECs? I can see they might be Luttinger Liquids,
>>>> but let's say it went one step further, not into a solid state of
>>>> matter but into the Condensate state of matter. Are there telltale
>>>> signs of a BEC?
>>>>
>>>
>>> I'm no fyzicist, but BECs are the quantum state of matter absolutely
>>> requiring the least possible amount of energy in the system as is possible
>>> (in order to overcome Pauli exclusion, AFAIK). So AFAIK too: they'd
>>> _necessarily_ *need* to be around zero kelvin. Not so superconductors:
>>> which would apparently *only* require a configuration which allows
>>> electrons (_only_ cooper pairs?) to travel freely without careening into
>>> the atomic lattice containing them. Perhaps a lattice which indeed *guides*
>>> them w/o any friction.
>>>
>>> Maybe a future fyzix would handle that at room temperature too... Who
>>> can know the far future, eh..? And perhaps room temperature superconductors
>>> would be the necessary pre-condition for that to come about, too... (??!!)
>>> :D
>>>
>>>
>>>
>>>
>>>>
>>>> On 7/18/17, Che <comandantegri...@gmail.com> wrote:
>>>> > On Wed, Jul 19, 2017 at 12:43 AM, Kevin O'Malley <kevmol...@gmail.com
>>>> >
>>>> > wrote:
>>>> >>
>>>> >> On Tue, Jul 18, 2017 at 7:13 AM, Brian Ahern <ahern_br...@msn.com>
>>>> wrote:
>>>> >>
>>>> >> There are no room temperature superconductors. They are theoretically
>>>> >> impossible.
>>>> >>
>>>> >> ***Someone should tell the guys who are working towards that goal.
>>>> >> https://en.wikipedia.org/wiki/Room-temperature_superconductor
>>>> >
>>>> >
>>>> > I think the problem with this sort of thinking, is that the
>>>> assumption is
>>>> > to assume we need only be looking at essentially 'known' states of
>>>> matter
>>>> > -- whilst totally overlooking the HUGE (essentially INFINITE) 'phase
>>>> space'
>>>> > of possibilities which 'emergent' physical relations hand us.
>>>> >
>>>> > Someone is not 'thinking outside the box'...
>>>> >
>>>>
>>>>
>>>
>>
>
