@article { ISI:000262360200027,
	title = {Measured long-range repulsive Casimir-Lifshitz forces},
	journal = {NATURE},
	volume = {457},
	number = {7226},
	year = {2009},
	month = {JAN 8},
	pages = {170-173},
	publisher = {NATURE PUBLISHING GROUP},
	type = {Article},
	address = {MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND},
	abstract = {Quantum fluctuations create intermolecular forces that pervade macroscopic bodies(1-3). At molecular separations of a few nanometres or less, these interactions are the familiar van der Waals forces(4). However, as recognized in the theories of Casimir, Polder and Lifshitz(5-7), at larger distances and between macroscopic condensed media they reveal retardation effects associated with the finite speed of light. Although these long- range forces exist within all matter, only attractive interactions have so far been measured between material bodies(8-11). Here we show experimentally that, in accord with theoretical prediction(12), the sign of the force can be changed from attractive to repulsive by suitable choice of interacting materials immersed in a fluid. The measured repulsive interaction is found to be weaker than the attractive. However, in both cases the magnitude of the force increases with decreasing surface separation. Repulsive Casimir - Lifshitz forces could allow quantum levitation of objects in a fluid and lead to a new class of switchable nanoscale devices with ultra-low static friction(13-15).},
	issn = {0028-0836},
	doi = {10.1038/nature07610},
	author = {Munday, J. N. and Federico Capasso and Parsegian, V. Adrian}
}
