Things not always run smoothly. It may happen, actually, that when an object slides on another, the advancement may occur through a 'stop and go' series in the characteristic manner which scientists call "stick-slip", a pervasive phenomenon at every scale, from earthquakes to daily-life objects, up to the "nano" dimension.
This image shows ions on an optical lattice.
Davide Mandelli, Andrea Vanossi and Erio Tosatti of the International School for Advanced Studies (SISSA) of Trieste have studied the conditions in which at the nanoscopic level the switch from smooth sliding to stick-slip regime occurs, simulating 'toy-like' systems of 'cold ions'.
"Our studies are based on the research on trapped cold ions. Before we did, such methodology had never been applied to the field of friction", explains Tosatti. "These are experimental studies I call 'toy-like' because they are models employed to explore reality, in the same way as a Lego little house may be used as the model of a real house. We have simulated such systems and used them in our field of research." Tosatti is the coordinator of the research, which appeared in the scientific journal Physical Review. The study, besides SISSA, also involves the Centro Democritos of Officina dei Materiali CNR-IOM.
More in detail…The three scientists have simulated the sliding of a one-dimensional ion chain of finite length on a substrate generated by laser beams (an optical lattice).
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