Chiral active metamaterials

Chiral active metamaterials

Soft Condensed Matter & Physics of Living Systems

Date

March 21, 2017 -
3:00pm to 4:00pm

Location

KLAUS

Room

1116 West

Affiliation

Leiden University, Netherlands

Active liquids are composed of self-driven microbots that endow the liquid with a unique set of mechanical characteristics. We design metamaterials using polar active liquids, i.e., liquids that flow spontaneously and without the need of external forcing. Specifically, we create chiral steady-state flow using periodically shaped microchannels. This induced flow gives rise to topologically protected density waves, which are robust against both disorder and backscattering. Furthermore, active liquids composed of self-spinning rotors are chiral by design, a feature reflected in their constitutive relations.

In two dimensions, the viscosity of such liquids includes an extra component called odd (or Hall) viscosity. Odd viscosity provides no energy dissipation, but couples pressure to vorticity. We explore how this coupling may be exploited to design self-assembled hydraulic cranks that convert between linear and rotational motion in microscopic machines powered by active rotors.