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Drop-on-demand printing applications involve a drop connected to a fluid reservoir between which volume can be exchanged, a situation that can be idealized as a sessile drop with prescribed volume flux across the drop/reservoir boundary. Here we compute the frequency spectrum for these pressure disturbances, as it depends upon the static contact-angle $$\alpha$$ (CA) and an empirical constant $$\chi$$ relating the reservoir pressure to volume exchanged, for either (i) pinned or (ii) free contact-lines. Mode shapes are characterized by the mode number pair $$[k,\ell ]$$ with property $$k+\ell =\mathbb {Z}^{+}_{odd}$$ that can be associated with the symmetry properties of the Rayleigh drop modes for the free sphere. We report instabilities to the axisymmetric $[1,0]$ and non-axisymmetric rocking $[2,1]$ modes that are related to centre-of-mass motions, and show how the spectral degeneracy of the Rayleigh drop modes breaks with the model parameters.
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Time-Domain Analysis of the Coupling between Free-Electrons and Photonic Waveguides
We investigate how free-electrons can excite modes in nearby photonic waveguides. Using particle-in-cell simulations, we explore how a free-electron packet can couple energy into multiple, velocity-matched modes of an adjacent silicon waveguide.
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- Award ID(s):
- 2110556
- PAR ID:
- 10550544
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- ISBN:
- 978-1-957171-39-5
- Page Range / eLocation ID:
- JW2A.197
- Format(s):
- Medium: X
- Location:
- Charlotte, North Carolina
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/CLEO_AT.2024.JW2A.197
