Correlated Disorder in Broadband Dielectric Multilayered Reflectors

A disordered one-dimensional photonic structure can be realized as a multilayer consisting of two different dielectric materials that alternate with random thicknesses. Generally, such a multilayer exhibits a wide reflection wavelength range in which, however, transmission notches that break the reflectance band continuity may be present due to stochastic resonances. Statistical analysis reveals that multilayers characterized by correlated disorder (i.e., thickness sequence presenting a non-negligible degree of autocorrelation) do not suffer from these stochastic resonances and behave as high-performance broadband reflectors.