Using direct laser writing polymer structures were added to the surface of a dielectric mirror, which served as one of the mirrors in a microcavity. The polymer provides a parabolic potential for the photons in the microresonator, and by varying the aspect ratio one can tune the dimensionality of the system. By radiative contact to a dye solution the photons are cooled down, and one onserves a thermal population of photons within the eigenmodes of the resonator. In two dimensions we observe a phase transition to a Bose-Einstein condensate, which first softens and then completely vanishes when crossing to one dimension, while the photon gas is still quantum degenerate. Our study appears in Nature Physics.
Additional Information:
Press release of the university
Nature Communities Blogpost
Homepage of the CRC/TR 185 "OSCAR"