Peierls state far from equilibrium

We show that a Peierls insulator under strong dynamic excitation of electron-hole pairs exhibits an instability into a mixed metal-insulator phase. This problem is analogous to the inhomogeneous nonequilibrium BCS state discussed by Scalapino and Huberman. We calculate the threshold parameters for typical Peierls insulators and discuss some organic systems that might be likely candidates for experimental verification. In contrast to the nonequilibrium superconductor, the mixed state in Peierls systems can be easily detected by light scattering techniques.