Cantilever tip-surface contact as a catastrophe machine

Self-organization of adatom adsorption structure at interaction with tip of dynamic force microscope

“…Nowadays, due to large scientific and practical importance, the phenomena taking place on the sample surface at interaction with the tip of a dynamic force microscope, e.g., atomic force microscope (AFM) and friction force microscope, attract more and more attention (see the reviews in [1][2][3][4][5][6] and the literature cited therein). Particularly, the experimental and theoretical data are obtained on structural instabilities, phase transformations, plastic dislocation, neck and adatom structures formation [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. These processes are characterized by hysteresis of dependencies of adhesion force and potential energy surface on the tipsurface distance [11,16,[21][22][23][24] and by hysteresis of the sample stress vs strain curve [25].…”

“…Since the nature of such phenomena remains poorly understood, the basic goal of the present study is the construction of a qualitative nonlinear model [26][27][28][29][30][31] describing the hysteresis processes which occur on the germanium surface during interaction with the AFM tip [11]. Here, the macroscopic continuum mechanics models [32,33] are supposed to be still applicable to the atomic length-scales, where discrete atomistic interactions become significant [3,16,18,34,35]. However, a total explanation of the studied macroscopic phenomena requires a consideration of microscopic processes.…”