title: Long-distance axial trapping with Laguerre-Gaussian beams.
abstract: We show that the axial spread of the focal volume of a tightly focused beam propagating through a glass-water interface is much reduced for Laguerre-Gaussian (LG) modes as compared to the TEM(00) mode. Therefore, use of the LG beam helps in achieving a significant improvement of the axial trapping range in optical tweezers. We demonstrate the use of LG modes to manipulate biological cells from the bottom layer of the medium to the top surface layer. Exposure of the cells to a higher oxygen concentration at the surface layer is used for estimation of the intramembrane oxygen diffusion rate.
authors: Laser Biomedical Applications and Instrumentation Division, Raja Ramanna Centre for Advanced Technology, Indore 452013, India. raktim@rrcat.gov.in
authors: Raktim
authors: R
authors: Dasgupta
authors: Ravi Shanker
authors: RS
authors: Verma
authors: Sunita
authors: S
authors: Ahlawat
authors: Deepa
authors: D
authors: Chaturvedi
authors: Pradeep Kumar
authors: PK
authors: Gupta
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives; D002460:Cell Line; D005456:Fluorescent Dyes; D006801:Humans; D007848:Laurates; D008863:Microspheres; D055620:Optical Phenomena; D052898:Optical Tweezers; D010100:Oxygen / Q000378:metabolism; D012822:Silicon Dioxide
chemical_list: D005456:Fluorescent Dyes; D007848:Laurates; D012822:Silicon Dioxide; D015081:2-Naphthylamine; D010100:Oxygen; C065580:laurdan