Inverse Peierls transition induced by photoexcitation in potassium tetracyanoquinodimethane crystals

Abstract
Photoinduced absorption spectra for vibrational and electronic excitations have been investigated in a prototypical one-dimensional Peierls-Hubbard system, potassium tetracyanoquinodimethane crystals. Strong photoinduced-absorption signals and their temperature-and time-dependent characteristics are discussed in terms of dynamics of a photoconverted molecular domains with no Peierls distortion in the background Peierls-distorted tetracyanoquinodimethane stacks. A close correlation between domain excitations and photoconductivity has also been confirmed.