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Time-averaged total force on a dipolar sphere in an electromagnetic field
Optics Letters
|December 8, 2007
Summary
We calculated the total force on tiny particles in time-varying fields. Including radiative reaction improves accuracy in modeling scattering forces, validating polarizability models.
Area of Science:
- Physics
- Nanotechnology
- Electromagnetism
Background:
- Subwavelength-sized particles interact with time-harmonic fields.
- Accurate force calculations are crucial for understanding particle behavior in fields.
Purpose of the Study:
- To establish the time-averaged total force on subwavelength particles in time-harmonic fields.
- To analyze the impact of radiative reaction on scattering force calculations.
- To evaluate existing polarizability models.
Main Methods:
- Theoretical analysis of forces on particles in time-varying fields.
- Inclusion of the radiative reaction term in polarizability calculations.
- Comparison and assessment of different polarizability models.
Main Results:
- A method to calculate the time-averaged total force on subwavelength particles is established.
- The radiative reaction term is shown to be essential for correctly accounting for scattering forces.
- The accuracy of various polarizability models is quantitatively assessed.
Conclusions:
- The developed framework provides a more accurate way to determine forces on nanoparticles.
- This work validates and refines the use of polarizability models in electromagnetic field interactions.
- Accurate modeling of scattering forces is critical for applications involving nanoparticles.
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