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Optical theorem for acoustic non-diffracting beams and application to radiation force and torque
Likun Zhang1, Philip L Marston
1Department of Physics and Center for Nonlinear Dynamics, University of Texas at Austin, Austin, TX 78712 USA.
Biomedical Optics Express
|September 20, 2013
Summary
Non-diffracting beams can manipulate objects. This study applies an extended optical theorem to calculate the extinction cross-section and radiation forces on a sphere using a Bessel beam.
Area of Science:
- Acoustics and Optics
- Wave Phenomena
- Particle Manipulation
Background:
- Non-diffracting beams, such as Bessel beams, offer unique properties for particle manipulation.
- An extended optical theorem relates an object's extinction to forward scattering of plane wave components.
- This theorem has been recently established in the context of acoustics.
Purpose of the Study:
- To apply the extended optical theorem to analyze acoustical and optical non-diffracting beams.
- To examine the extinction cross-section of a sphere illuminated by a non-diffracting Bessel beam.
- To determine the axial radiation force and torque exerted on the sphere.
Main Methods:
- Utilizing an extended optical theorem for non-diffracting beams.
- Calculating the extinction cross-section of a sphere positioned on the beam axis.
- Applying the results to derive radiation force and torque.
Main Results:
- The study successfully applies the extended optical theorem to a Bessel beam.
- The extinction cross-section of a sphere was analyzed.
- Axial radiation force and torque on the sphere were recovered.
Conclusions:
- The extended optical theorem provides a framework for understanding beam-object interactions.
- Bessel beams can exert significant axial radiation forces and torques on spheres.
- This research contributes to the understanding of non-diffracting beam applications in particle manipulation.
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