3D characterization of the forces in optical traps based on counter-propagating beams shaped by a spatial light modulator

Martin V. Kristensen; Thue B. Lindballe; Anton P. Kylling; Darwin Z. Palima; Jesper Glückstad; Soren R. Keiding; Henrik Stapelfeldt

doi:10.1117/12.866479

27 August 2010 3D characterization of the forces in optical traps based on counter-propagating beams shaped by a spatial light modulator

Martin V. Kristensen, Thue B. Lindballe, Anton P. Kylling, Darwin Z. Palima, Jesper Glückstad, Soren R. Keiding, Henrik Stapelfeldt

Author Affiliations +

Proceedings Volume 7762, Optical Trapping and Optical Micromanipulation VII; 77623E (2010) https://doi.org/10.1117/12.866479
Event: SPIE NanoScience + Engineering, 2010, San Diego, California, United States

Abstract

An experimental characterization of the 3D forces, acting on a trapped polystyrene bead in a counter-propagating beam geometry, is reported. Using a single optical trap with a large working distance (in the BioPhotonics Workstation), we simultaneously measure the transverse and longitudinal trapping force constants. Two different methods were used: The Drag force method and the Equipartition method. We show that the counterpropagating beams traps are simple harmonic for small displacements. The force constants reveal a transverse asymmetry as κ_- = 9.7 pN/μm and κ₊ = 11.3 pN/μm (at a total laser power of 2x35 mW) for displacements in opposite directions. The Equipartition method is limited by mechanical noise and is shown to be applicable only when the total laser power in a single 10 μm counter-propagating trap is below 2x20 mW.

Citation Download Citation

Martin V. Kristensen, Thue B. Lindballe, Anton P. Kylling, Darwin Z. Palima, Jesper Glückstad, Soren R. Keiding, and Henrik Stapelfeldt "3D characterization of the forces in optical traps based on counter-propagating beams shaped by a spatial light modulator", Proc. SPIE 7762, Optical Trapping and Optical Micromanipulation VII, 77623E (27 August 2010); https://doi.org/10.1117/12.866479

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available