CPM Seminar

The study of crystalline surfaces in real space with atomic resolution is the prominent feature of force microscopy. Recent results in the contact mode include the demonstration of atomic-scale stick-slip on clean metal surfaces and the measurement of the velocity dependence of atomic friction. In the non-contact mode, step and kink sites of NaCl films grown on Cu(111) have been resolved. The increased tip-sample interaction found at low-coordinated sites stimulates the interest in measuring forces on the atomic scale. Schemes for the separation of long-range and short-ranged chemical forces are discussed. In dynamic modes of force microscopy, the damping of the cantilever oscillation can be used to study dissipative tip-sample interactions. The comparison of dissipation in friction and in non-contact experiments might open new perspectives on energy loss processes on the atomic scale.

Monday, April 23rd 2001, 15:30
Ernest Rutherford Physics Building, Boardroom (room 104)