Atomic force microscopy
Atomic force microscopy (AFM) is a powerful, universal technique capable of imaging almost any surface type, from polymers, ceramics, and composites to delicate biological samples. But the modern goal extends beyond simple topography; researchers now use AFM to measure and localize specific physical forces—including adhesion strength, magnetic fields, and mechanical properties—with nanometer precision. The measurement relies on a sharp tip, approximately 10 to 20 nm in diameter, interacting with the sample. The physics of this tip-surface interaction is inherently non-linear. While this non-linearity makes the signal complex, it also encodes the rich material properties of the surface. The challenge lies in capturing enough of this complex signal to accurately decode those properties, which requires analyzing the cantilever's response far beyond the fundamental frequency. Standard controllers often miss this rich data. To fully exploit the non-linear response, we developed the Multifrequency AFM kit and the MLA-3 Multifrequency lock-in amplifier. This platform can simultaneously measure up to 32 harmonics of the cantilever’s motion, providing a complete picture of the interaction. By capturing these higher harmonics, our system enables you to extract surface properties faster and with significantly better sensitivity. See how this multi-harmonic approach is driving new research in the application notes below.
