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Abstract Magnetic liquid metal (MLM) is a mixture of magnetic particles with gallium‐based liquid metals which utilizes an unconventional combination of fluidity, high thermal/electrical conductivity, biocompatibility, and magnetism. Recently, from materials to applications, studies on MLMs have drastically increased. Single or multiple MLMs can be precisely positioned or can act as a carrier for handling other objects. MLMs are also used in biomedical applications such as cancer treatment by hyperthermia and precision delivery of cancer drugs on tumors, or antibacterial coating which kills bacteria. In electronics applications, MLMs are used for magnetic field‐driven patterning of metallic lines, reconfigurable interconnects, electronic tattoos, and reconfigurable electromagnetic wave shielding. Phase change (solid/liquid) of MLMs adds another unique capability, morphing. A combination of innovations in the micro/nano robots and MLMs has huge potential to bring an unprecedented disruptive technology for a wide variety of applications including self‐morphing shape‐recovery robots, highly localized cancer treatment, and reconfigurable stealth/camouflage, among others. This article comprehensively reviews recent developments in MLMs from the materials to methods of preparation, locomotion of MLMs, their applications, and future outlooks.
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Enabling Reconfigurable All-Liquid Microcircuits via Laplace Barriers to Control Liquid Metal
Liquid metals such as gallium alloys have a unique potential to enable fully reconfigurable RF electronics. One of the major concerns for liquid-metal electronics is their interaction with solid-metal contacts, which results in unwanted changes to electrical performance and delamination of solid-metal contacts due to atomic diffusion of gallium at the liquid/solid interface. In this paper, we present a solution to this problem through way of liquid-metal/liquid-metal RF connections by implementing Laplace barriers, which control fluid flow and position via pressure-sensitive thresholds to facilitate physical movement of the fluids within the channels. We demonstrate RF switching within the channel systems by fabricating, testing, and modeling a reconfigurable RF microstrip transmission line with integrated Laplace barriers which operates between 0.5–5 GHz. This approach opens the potential for future all-liquid reconfigurable RF electronic circuits where physical connections between solid and liquid metals are minimized or possibly eliminated altogether.
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- Award ID(s):
- 1807896
- PAR ID:
- 10099099
- Date Published:
- Journal Name:
- IEEE MTT-S International Microwave Symposium digest
- ISSN:
- 0149-645X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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