Eloisa Bentivegna
Big Data 2022
Using an off resonance ac technique in ultrahigh vacuum we have directly measured the force-gradient interaction characteristics of a gold tip and sample and demonstrated a new atomic force microscope imaging mode with the tip located very close to the surface. The method involves the application of a small sinusoidal oscillating force to the tip via a magnetic field created by a conducting coil which interacts with a magnetic particle glued on the backside of the cantilever. By measuring the change in amplitude during the approach and retraction of the sample we have a continuous and accurate measure of the force gradient. The interaction potential is thus found without the need for complex analysis as is necessary in the case of the commonly used technique of measuring frequency shifts.
Eloisa Bentivegna
Big Data 2022
Q.R. Huang, Ho-Cheol Kim, et al.
Macromolecules
Thomas E. Karis, C. Mark Seymour, et al.
Rheologica Acta
Michael Ray, Yves C. Martin
Proceedings of SPIE - The International Society for Optical Engineering