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Updated: May 14, 2026
13:39
Optical Trapping of Nanoparticles
Published on: January 15, 2013
Transition of a particle between adjacent optical traps: a study using catastrophe theory
Deepak Kumar1, Shankar Ghosh, S Bhattacharya
1Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400-005, India.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 16, 2013
Summary
Researchers developed a novel method using optical tweezers to precisely measure forces. This technique validates optical trap performance and maps force-displacement curves, crucial for quantitative biophysics and nanotechnology applications.
Area of Science:
- Physics
- Biophysics
- Nanotechnology
Background:
- Optical tweezers are widely used for measuring small forces.
- A validated and simple experimental method for parameterizing optical tweezers is lacking.
Purpose of the Study:
- To develop an unambiguous experimental method for validating and parameterizing optical tweezers.
- To determine the force-displacement curve of an optical trap over its entire range.
Main Methods:
- Studying the transition of a colloidal particle between two spatially separated optical traps.
- Analyzing the transition as a function of relative trap intensity and separation.
Main Results:
- The particle transition exhibited a formal resemblance to the "butterfly catastrophe".
- This phenomenon is analogous to phase transitions in other systems like ferroelectrics.
- The method successfully determined the force-displacement curve for an optical trap.
Conclusions:
- A novel, simple, and unambiguous experimental method for optical tweezer calibration has been established.
- The study provides a validated approach for empirically parameterizing optical traps.
- This method has broad implications for quantitative force measurements in various scientific fields.
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