Polariton superfluid

Polariton superfluid is predicted to be a state of the exciton-polariton system that combines the characteristics of lasers with those of excellent electrical conductors. Researchers look for this state in a solid state optical microcavity coupled with quantum well excitons. The idea is to create an ensemble of particles known as exciton-polaritons and trap them. Wave behavior in this state results in a light beam similar to that from a laser but possibly more energy efficient.

Unlike traditional superfluids that need temperatures of approximately -450 degrees Fahrenheit, the polariton superfluid could in principle be stable at much higher temperatures, and might soon be demonstrable at room temperature. [Cite web |url=http://mac10.umc.pitt.edu/m/FMPro?-db=ma&-lay=a&-format=d.html&id=2936&-Find|title=Pitt Researchers Create New Form of Matter|work=Morgan Kelly|publisher=University of Pittsburgh|accessdate=2007-05-31]

Claims of the polariton superfluid appeared in the May 18, 2007, issue of the journal "Science" by David Snoke, an associate professor in the physics and astronomy department in the University of Pittsburgh School of Arts and Sciences. [Cite web |url=http://www.sciencemag.org/cgi/reprint/316/5827/949c.pdf|title=Rubble Pile in Space|work=Stella Hurtley, Phil Szuromi|publisher=American Association for the Advancement of Science |accessdate=2007-05-31] Prof. Snoke worked with University of Pittsburgh graduate students Ryan Balili and Vincent Hartwell on the project and their collaborators at the Bell Labs of Alcatel-Lucent in New Jersey.

Although several other researchers are working in the same field, [cite paper
author = Jacek Kasprzak
title = Condensation of exciton polaritons
publisher = Université Joseph-Fourier - Grenoble I
date = 2006
url = http://tel.archives-ouvertes.fr/docs/00/11/83/16/PDF/Kasprzak_Jacek.pdf
format = PDF
accessdate = 2006-10-14 ] [cite paper
author = Hui Deng
title = Dynamic Condensation of Semiconductor Microcavity Polaritons
publisher = Stanford University
date = 2006
url = http://www.stanford.edu/group/yamamotogroup/Thesis/HDthesis.pdf
format = PDF
accessdate = 2006-10-14 ] the Pittsburgh group terminology and conclusions are not completely shared by them.In particular, important properties of superfluids, such as zero viscosity, and of lasers, such as perfect optical coherence, are a matter of debate.

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