Phys.
Rev. Lett. 88, 226401 (2002)
(Received 19 June 2001; published 15 May 2002)
We observed photoinduced quantum interference antiresonances between several discrete infrared-active vibrations and the lower-polaron continuous absorption band in a series of -conjugated polymer films having superior planar orders, where the polaron transition energy is relatively small. The photoinduced Fano-type antiresonances are well explained by extending the amplitude mode model beyond the adiabatic limit. The agreement between the data and the model confirms the presence of a continuous electronic band above the polaron state. We show that high frequency modes are strongly coupled to electrons, with implications for superconductivity. ©2002 The American Physical Society
PACS: 71.38.-k, 63.22.+m, 78.30.Jw