Electronic energy relaxation and transition frequency jumps of single molecules at 30 mK.

Transition frequency jumps for single terrylene molecules in a polyethylene matrix caused by resonant laser irradiation are investigated at 30 mK. These jumps are not accompanied by substantial sample heating. A model for the effect is proposed, based on the interaction of tunneling two-level systems (TLSs) surrounding the single molecule with high-energy nonthermal phonons emitted by the molecule during electronic energy relaxation. The radius of the effective interaction volume is estimated to be r(m) approximately 12.5 nm, and the interaction cross section for nonequilibrium phonon-TLS scattering is estimated as approximately 10(-22) cm2.