Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE
Can self-focusing of intense photon beams cause Bose-Einstein condensation into a superfluid state?
Friedwardt Winterberg
Abstract
The cause of the phenomenon of self-focusing of intense laser beams is the nonlinear intensity dependent refractive index of optical materials. This property which leads to the self-focusing can be interpreted as an attractive force in between the photons thereby increasing the photon density. For large enough densities the photon gas may undergo Bose-Einstein condensation and if the attractive force is strong enough may even become a superfluid through a second order phase transition. This mechanism not possible for free photons is possible inside optical materials with a large refractive index because there the photons can be viewed as massive quasiparticles having a velocity less than the velocity of light. With the large dielectric constants of certain ferroelectric substances valid in the range of microwave frequencies the envisioned process might even work with microwave photons. This would make possible the generation of very intense highly coherent microwave beams. I .