Measurement of three dimensional polarization direction in ferroelectric thin films using scanning nonlinear dielectric microscopy with rotating electric field

A scanning nonlinear dielectric microscope (SNDM) probe, called the ε₃₁₁-type probe, and a system to measure the ferroelectric polarization component parallel to the surface using rotating electric field have been developed. This is achieved by measuring the ferroelectric material's nonlinear dielectric constant ε₃₁₁ instead of ε₃₃₃, which is measured in conventional SNDM. Experimental result shows that we can successfully determine polarization component parallel to the surface. The SNDM system can measure polarization at any angle from the surface normal which is often of interest.