AMPLIFICATION OF COHERENT POLAR VIBRATIONS IN BIOPOLYMERS - FROHLICH CONDENSATE

We consider the nonequilibrium and dissipative evolution, and the stea dy state of the population of vibrational polar modes in a chain of bi omolecules. These polar modes are excited through a coupling with a me tabolic pumping source and are in anharmonic interaction with an elast ic continuum. Groups of polar modes are coupled in this way through no nlinear terms in the kinetic equations. This nonlinearity is shown to be the source of an unexpected phenomenon characterizing complex behav ior in this kind of system: after a threshold of intensity of the pump ing source is achieved, polar modes with the lowest frequencies increa se enormously their population in a way reminiscent of a Bose-Einstein condensation (Frohlich effect). The transient time for the steady-sta te condensate to follow is very short (picosecond time scale) and the condensation appears even for weak values of the anharmonic coupling s trength responsible for its occurrence. Further, it seemingly requires accessible levels of metabolic pumping power in order to be produced and sustained.