Study of propagation-invariant beams and its application in optical tweezers for micromanipulation
Balpreet Singh Ahluwalia
Date of Issue2007
School of Electrical and Electronic Engineering
Optical tweezers is a laser enabled non-invasive technique for micromanipulation of the microscopic sized particles. The momentum transferred by a highly focused laser beam is used to trap the micro-particles in three-dimensions. Laser micro-beam shaping directly enhances the trapping capability of the optical tweezers system. In this quest, researchers introduced the propagation-invariant beams in optical tweezers system. Such propagation-invariant beams are also referred as non-diffracting or Bessel beams and possess the distinct property of propagation-invariance of its core for a finite distance. Another interesting property of Bessel beams is the self-reconstruction of an obstructed or distorted Bessel beam along the propagation axis. These unique properties of the nondiffracting beams have been successfully exploited for optical manipulations in the optical tweezers system. In this thesis, various novel propagation-invariant fields are studied and employed for diversified optical trapping applications.
DRNTU::Engineering::Electrical and electronic engineering::Optics, optoelectronics, photonics