The LIMM problem for ferroelectric thin films comprising space charge layers

In this work, the laser intensity modulation method (LIMM) problem is reconsidered for the generalized case of a multilayer structure consisting of layers with ferroelectric polarization, with both ferroelectric and space charge induced polarization, and with solely space charge induced polarization. Usually, the problem reduces to the calculation of the internal electric field. Boundary conditions are derived from the electric displacement of a short-circuited structure. The calculations were compared with the pyroelectric spectrum of PZT thin films of different thickness and a model metal–ferroelectric–semiconductor structure consisting of Pt–ferroelectric PZT (perovskite)–semiconducting PZT (fluorite).