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Optics Letters

Optics Letters


  • Vol. 36, Iss. 8 — Apr. 15, 2011
  • pp: 1497–1499

Ensemble method to measure the potential energy of nanoparticles in an optical trap

Joseph Junio, Jack Ng, Joel A. Cohen, Zhifang Lin, and H. Daniel Ou-Yang  »View Author Affiliations

Optics Letters, Vol. 36, Issue 8, pp. 1497-1499 (2011)

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A method is described for measuring the potential energy of nanoparticles in an optical trap by trapping an ensemble of particles with a focused laser beam. The force balance between repulsive osmotic and confining gradient-force pressures determines the single-particle trapping potential independent of interactions between the particles. The ensemble nature of the measurement permits evaluation of single-particle trapping energies much smaller than k B T . Energies obtained by this method are compared to those of single-particle methods as well as to theoretical calculations based on classical electromagnetic optics.

© 2011 Optical Society of America

OCIS Codes
(350.4990) Other areas of optics : Particles
(350.4855) Other areas of optics : Optical tweezers or optical manipulation

ToC Category:
Optical Tweezers or Optical Manipulation

Original Manuscript: November 9, 2010
Revised Manuscript: March 4, 2011
Manuscript Accepted: March 5, 2011
Published: April 15, 2011

Virtual Issues
Vol. 6, Iss. 5 Virtual Journal for Biomedical Optics

Joseph Junio, Jack Ng, Joel A. Cohen, Zhifang Lin, and H. Daniel Ou-Yang, "Ensemble method to measure the potential energy of nanoparticles in an optical trap," Opt. Lett. 36, 1497-1499 (2011)

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