Control of active nematics via viscoelastic confinement*

Active nematic systems display turbulent-like motion when unconstrained. While this chaotic motion can be controlled in space by geometric confinement, achieving temporal control remains an open challenge. I will consider the dynamics of an active nematic confined in a channel made of viscoelastic material. For soft channels, the system produces spontaneous oscillations with periodic flow reversals. Notably, the temporal frequency of the oscillations can be manipulated by altering the mechanical properties of the surroundings, offering a guiding principle to control the dynamical behavior of active materials.