@article { PinyuPRL09,
	title = {Direct Measurement of the Nonconservative Force Field Generated by	Optical Tweezers},
	journal = {Phys. Rev. Lett.},
	volume = {103},
	year = {2009},
	pages = {108101},
	keywords = {MF},
	doi = {10.1103/PhysRevLett.103.108101},
	author = {Wu, Pinyu and Huang, Rongxin and Tischer, Christian and A. Jon{\'a}{\v s} and Florin, Ernst-Ludwig}
}
