My research includes nonequilibrium dynamics of internally driven active polymers, chemomechanical transduction in chemically active elastic sheets, and dynamic self-organization of microparticles using active and driven fluids. Using computer simulations, we investigate different toplogical phenomena in active polymers for examples motile defects, the nonequilibrium transition between isotropic and liquid crystalline states, and the dynamic formation of knots and links . We also harnessed chemically generated fluid flow to perform self-sustained operations in elastic sheets, including self-morphing, self-rotating, and self-oscillating behavior. We also employ light- and chemically driven fluid pumping for dynamic control over the motion of immersed microparticles, including the formation and transport of reversible particle assemblies, as well as the separation of different sized particles in the fluidic chambers.

The ability to translate chemical cues into mechanical action is a defining feature of living organisms. Inspired to create materials that exhibit analogous ``life-like” behavior, we focus on chemically active two dimensional sheets which is driven by self-induced fluid flows. In contrast to active hard spheres, a two dimensional sheet is sufficiently flexible that the flowing fluid drives not only the propulsion, but also the shape evolution of the sheet, transforming the 2D layer into a moving, three dimensional object. Moreover, the transported, evolving sheet affects the flow of the surrounding fluid. Hence, chemically active materials of higher dimensionality and increased flexibility can exhibit rich, cooperative interactions.

• Manna et al, Mater. Horiz. 7, 2314 (2020)
• Manna et al, Proc. Natl. Acad. Sci. U.S.A. 118, 12 (2021)
• Manna et al, Nat. Rev. Phys. 1-13 (2021)

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Active polymers are composed of units which can produce fluid flow around it. Depending on the nature of the activity and the domain, the polymers produce a series of spontaneous motion. For instance, extensile semiflexible polymers produce autonomous motion driven by the active flows and contractile polymers shows rotational motion when confined in a spherical cavity. Our study fouces on the collective dynamics of active polymers in confined geometry and demonstrates the dynamic formation of knots and links, nonequilibrium transition between isotropic and liquid crystalline states and athermal creation and annihilation of different kind of defects. Moreover, the non-equilibrium fluid flows produced by atcive polymers can be harnessed with smart designs to transport vesicles ballistically.

• Manna et al, J. Chem. Phys. 146 , 024901 (2017)
• Biswas et al, ACS Nano 11, 10 (2017)
• Manna et al, Soft Matter 15, 477 (2019)

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Micropumps that propel fluids using energy derived from chemical reactions or photothermal effects can regulate the assembly and segregation of microparticles in solution. In both chemical and light-driven micropumps, fluid pumping occurs via three different mechanisms: thermal buoyancy, solutal buoyancy and diffusioosmosis. These pumping mechanisms can operate simultaneously and the combination of two or more mechanisms leads to complex fluid flow patterns that enables dynamic control over the motion of immersed microparticles.

• Manna et al, ACS Appl. Mater. Interfaces 11 , 19 (2019)
• Tansi et al, ACS Appl. Mater. Interfaces 13 , 5 (2021)
• Kauffman et al, ChemNanoMat 7, 805 (2021)
• Manna et al, Langmuir 38, 4, (2022)

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