Abstract

When an intense nonresonant field interacts with a two-level system, the wavefunctions are modified. Several approaches may be used to study this problem including the techniques of dressed state theory. When the two-level system is comprised of two midgap sites separated by a distance R_ab and an energy in the absence of light shifts W_ba, the light shifted energy separation becomes This effect acts on level pairs and therefore shifts all the energy levels closer to each other. With these results and the rough criteria for Anderson localization W > B (B is the energy bandwidth), we may arrive at a condition for which a transition from localized to extended states could occur. The resulting critical intensity is given by Using typical values of R = 15 Å, v = 3 ×10¹⁴ Hz, α = 0.2 AX⁻¹, and W = 0.4 eV, we arrive at critical intensity for delocalization of I_c= 10GW/cm².

© 1989 Optical Society of America