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A liquid-metal intelligent reflecting surface (IRS) unit cell is presented, using hybrid electrocapillary actuation to enable reconfigurability. Elongation of the liquid metal by up to 4 mm is experimentally demonstrated, corresponding to a ~ 180° reflection phase shift between two unit-cell states. Simulation of a 7 × 6 IRS array based on these two unit-cell states results in non-specular reflected signals at 4.85 GHz that are indicative of IRS functionality.
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Electrocapillary Actuation of Liquid Metal in Microchannels
Controllable deformation of liquid metal by electrocapillary actuation (ECA) is empirically characterized in fluidic channels at the sub-millimeter-length scale. In 100-µm-deep channels of varying widths, the Galinstan liquid metal could move at velocities of more than 40 mm/s. The liquid metal could extend more than 2.5 mm into the channels at an electrocapillary actuation voltage of 3 V DC. The dynamic behavior of the liquid metal as it moves in the microchannels is described. These results are useful for designing microsystems that use liquid metal as a functional material.
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- Award ID(s):
- 1807896
- PAR ID:
- 10345682
- Date Published:
- Journal Name:
- Micromachines
- Volume:
- 13
- Issue:
- 4
- ISSN:
- 2072-666X
- Page Range / eLocation ID:
- 572
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/mi13040572
