Anderson localization of light in two-dimensional random media

Light propagation in two-dimensional random configurations of dielectric cylindrical columns adopting parameters of gallium nitride nanocolumns via the finite-difference time-domain method is simulated. The sample area is 5 μm square (L_sys= 5 μm), and consists of an array of the parallel columns with a constant radius (R = 50 nm) and a constant refractive index (n= 2.4). The columns are placed randomly not to touch each other, and they are embedded in vacuum. Under these conditions, the localization effect depends only on the column filling fraction Φ and the light frequency f. In the simulation, a transverse magnetic white pulse onto the center of the system is irradiated, and the temporal evolution of the field is recorded. The photon lifetime of the system at several frequencies τ(f) by Fourier analysis is then calculated.