Welcome to the Carpick lab web page. We are interested in studying mechanics and
tribology (friction, adhesion, lubrication, wear) at the atomic / molecular / nanometer
scale. We are developing advanced scanning force microscopy tools to investigate the
interactions that take place at contacting, sliding interfaces. We are particularly
interested in applying these tools to novel materials with exceptional properties for
new applications.
Friction, for example, is perhaps the most common yet least understood physical
phenomenon. We aim to develop fundamental insight into its origin.
While this work is fundamental in nature, there are numerous important applications.
It is crucial to understand surface-dominated forces like friction and adhesion for
micro- and nano-scale devices, such as micro-electro-mechanical systems (MEMS), which
possess a large surface-to-volume ratio.
An atomic force microscope (AFM) consists of a cantilever and integrated
tip. The tip makes contact with a sample's surface. A laser beam, focused on the
back of the cantilever, reflects into a quadrant photodetector. Normal and lateral
forces deflect the cantilever, and these deflections are measured by monitoring
the photodetector signal. This allows force detection in the nanoNewton to
picoNewton (10-9 to 10-12 N) regime. |
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Friction map, 7.5 x 7.5 nm2:
atomic-scale stick-slip between a silicon tip and a potassium fluoride single crystal
surface.
Topographic map, 600 x 600 nm2:
single atomic steps and dislocations (white arrows) emerging at the surface of potassium
chloride (001).
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