title: Optical orientation and rotation of trapped red blood cells with Laguerre-Gaussian mode.
abstract: We report the use of Laguerre-Gaussian (LG) modes for controlled orientation and rotation of optically trapped red blood cells (RBCs). For LG modes with increasing topological charge the resulting increase in size of the intensity annulas led to trapping of the cells at larger tilt angle with respect to the beam axis and thus provided additional control on the stable orientation of the cells under trap. Further, the RBCs could also be driven as micro-rotors by a transfer of orbital angular momentum from the LG trapping beam having large topological charge or by rotating the profile of LG mode having fractional topological charge.
authors.affiliation: Laser Biomedical Applications and Instrumentation Division, Raja Ramanna Centre for Advanced Technology, Indore-452013, India. raktim@rrcat.gov.in
authors.forename: Raktim
authors.initials: R
authors.lastname: Dasgupta
authors.forename: Sunita
authors.initials: S
authors.lastname: Ahlawat
authors.forename: Ravi Shankar
authors.initials: RS
authors.lastname: Verma
authors.forename: Pradeep Kumar
authors.initials: PK
authors.lastname: Gupta
mesh_terms: D002021:Buffers; D004867:Equipment Design; D004906:Erythrocyte Count / Q000379:methods*; D004912:Erythrocytes / Q000166:cytology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007834:Lasers; D008853:Microscopy / Q000379:methods; D016011:Normal Distribution; D052898:Optical Tweezers; D055095:Optics and Photonics; D010825:Physics / Q000379:methods; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013696:Temperature
chemical_list: D002021:Buffers