PIs: Fink, Joannopoulos
The realization of multifunctional fiber devices into fabrics could enable unobtrusive, low-profile, and lightweight functionalization of soldier uniforms to perform sophisticated mission enabling tasks. The objective of this proposal is to research and discover a suite of novel fiber and fabric capabilities for high bandwidth communications and thermal IR signature management. Leveraging on previous advances in multimaterial preform-to-fiber drawing, here the focus is on establishing three new classes of foundational capabilities that will enable unique fiber-device functionalities. First, researchers will investigate methods for incorporating existing electronic devices such as LEDs and photodiodes into fibers, utilizing the fiber drawing as a packaging and metallization approach for high volume high performance fiber devices. These devices will be incorporated into the preform and thermally drawn but, unlike all previous preform-to-fiber drawing approaches reported to date, these devices will not themselves undergo shear flow during the drawing process. Instead, these embedded devices will flow in the heterogeneous solid/fluid flow with well-controlled orientation of the solid-state domains. This will enable a host of active fiber and fabric systems that could function as both fiber and fabric-based optical transmitters and receivers. Second, the team will study controlled induction of in-fiber fluid instabilities as a means for delivering intra-fiber materials self-assembly and functionalization of different semiconductor materials, including silicon, germanium, and selenium. This will open the path to new fiber architectures and functions. For example, capillary instability will be used to break up fiber-embedded cylindrical photodetectors into spherical ones, thus enabling resonant-enhanced absorption, higher responsivity and higher bandwidth optical detection. Third, researchers will investigate new fiber architectures and paradigms for fabric communications and thermal IR signature management. This effort will include the study of new mechano-optic, electro-optic, thermo-optic, and thermoelectric fiber architectures.