Atomic scale friction: from basic characteristics to control

The basic characteristics of molecular systems under shear are briefly revi ewed and methods to control friction are proposed. These control methods al low to eliminate chaotic stick-slip motion, and modify frictional forces. T he possibilities to control friction are demonstrated using a model system which displays the main experimentally observed behaviors, obtained in meas urements on nanoscale confined liquids and granular layers. The methods sho uld be applicable to real systems for which time series of dynamical variab les are experimentally available. The only necessary condition is the exist ence of (possibly unstable) sliding regimes of motion in experimental syste ms. (C) 1999 Elsevier Science B.V. All rights reserved.