TITLE:
Variation of Trapping Strength with Size and Number of Particles in a Single Trap
AUTHORS:
Jitendra Bhatt, Sachin Bhatt, Shaival Buch, Ravindra Pratap Singh, Saiyed Nisar Ali Jaaffrey
KEYWORDS:
Optical Tweezers; Multiple Particles; Trapping Strength
JOURNAL NAME:
Optics and Photonics Journal,
Vol.3 No.2,
June
7,
2013
ABSTRACT: Optical tweezers use the radiation pressure to trap and
manipulate the microscopic particles. Using various algorithms multiple traps
are being formed which can trap a number of particles simultaneously. In contrast
to multiple traps, many particles can be trapped at a single trap position. It
is known that when two or more particles are trapped in a single trap they align
themselves in axial direction and it appears as if only one particle is
trapped. We present a study of the dependence of the optical trapping force on
the number of particles in a single trap using equipartition method; the study
was carried out for particles of different sizes. The trapping force was first
found to increase then decrease with number of particles in trap for all
particle sizes. We feel that our studies will be useful in applications of optical tweezers involving
trapping of multiple particles in a single trap.