@article {42615,
	title = {Friction of a slider on a granular layer: non-monotonic thickness dependence and effect of boundary conditions},
	journal = {Physical Review E},
	volume = {73},
	year = {2006},
	month = {JAN},
	pages = {010301},
	type = {Article},
	abstract = {<p>We investigate the effective friction encountered by a mass sliding on a granular layer as a function of bed thickness and boundary roughness conditions. The observed friction has minima for a small number of layers before it increases and saturates to a value that depends on the roughness of the sliding surface. We use an index-matched interstitial liquid to probe the internal motion of the grains with fluorescence imaging in a regime where the liquid has no significant effect on the measured friction. The shear profiles obtained as a function of depth show a decrease in slip near the sliding surface as the layer thickness is increased. We propose that the friction depends on the degree of grain confinement relative to the sliding surfaces.</p>},
	doi = {10.1103/PhysRevE.73.010301},
	author = {Siavoshi, Saloome and Orpe, Ashish V. and Kudrollim, Arshad}
}
