Refined force-velocity relation in atomic friction experiments
Refined force-velocity relation in atomic friction experiments
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原子摩擦实验中精细的力-速度关系
DOI：
10.1103/physrevb.73.113401
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发表时间：
2006
影响因子：
3.7
通讯作者：
P. Reimann
中科院分区：
文献类型：
--
作者：
M. Evstigneev;P. Reimann
与均匀移动表面接触的原子力显微镜尖端的粘滑运动由尖端被限制在移动表面位置之一时的粘着相和尖端从一个位置到下一个位置的热激活滑移组成。粘滞阶段与悬臂弹簧、尖端顶点和接触区域表面的弹性变形的增加有关。相应的弹簧常数是根据弹力的增加率通过实验确定的。通过考虑尖端-表面相互作用势的影响，我们改进了实验测量的弹簧常数的表达式，并表明它弱依赖于拉力速度。我们将该表达式合并到先前在速率理论中获得的力-速度关系中，并证明这种改进可以显着提高该关系的准确性。
The stick slip motion of an atomic-force-microscopy tip in contact with a uniformly moving surface consists of the stick phases when the tip is confined to one of the moving surface sites and thermally activated slips of the tip from one site to the next. The stick phase is associated with the increase of the elastic deformation of the cantilever spring, the tip apex, and the surface in the contact region. The corresponding spring constant is experimentally determined from the rate of increase of the elastic force. By taking into account the effect of the tip-surface interaction potential, we refine the expression for the experimentally measured spring constant and show that it weakly depends on the pulling velocity. We incorporate this expression into the force-velocity relation obtained previously within the rate theory and demonstrate that such a refinement leads to a notable improvement of the accuracy of this relation.