HYSTERESIS GENERATED BY ATTRACTIVE INTERACTION - OSCILLATING BEHAVIOROF A VIBRATING TIP-MICROLEVER SYSTEM NEAR A SURFACE

We provide experimental evidence of hysteretic behavior of a vibrating microlever that arises when a surface approaches the microlever. An a nalytical solution is derived from a variational method that shows tha t the width of the hysteresis depends on the strength of the attractiv e interaction at a given driving amplitude. For a large attractive int eraction, the hysteretic behavior disappears, and the oscillating ampl itude of the microlever decreases as the tip is close to the surface w ithout needing to touch the surface. As a direct consequence, the way the cycle of the hysteresis varies close to the surface can be used to measure the change in attractive interaction without disturbing the s urface. (C) 1998 Elsevier Science B.V. All rights reserved.