Photoinjected plasma in semiconductor quantum wires: Soft-like upper plasmon

We consider the steady-state photoinjected two-component plasma in quasi-on e-dimensional semiconductor materials, generated by c.w. UV-light illuminat ion. We analyze the two types of carrier's collective elementary excitation s in this far-from-equilibrium dissipative system. It is predicted that at a critical level of excitation there follows a phenomenon consisting in a d rastic change of behavior in the propagation of the so-called upper plasma waves.