Zilch vortical effect, Berry phase, and kinetic theory

Rotating photon gas exhibits a chirality separation along the angular velocity which is manifested through a generation of helicity and zilch currents. In this paper we study this system using the corresponding Wigner function and construct elements of the covariant chiral kinetic theory for photons from first principles. The Wigner function is solved order-by-order in ħ and the unconstrained terms are fixed by matching with quantum field theory results. We further consider the zilch and helicity currents and show that both manifestations of the chirality transport originate in the Berry phase of photons similarly to other chiral effects. Constructing the kinetic description from the Wigner function we find that the frame vector needed to fix the definition of spin of a massless particle is, in fact, the vector of the residual gauge freedom for the free Maxwell theory. We also briefly comment on the possible relation between vortical responses in rotating systems of massless particles and the anomalies of underlying quantum field theory.

Ethanol-assisted gel chromatography for single-chirality separation of carbon nanotubes

Ethanol tunes the interaction of carbon nanotubes with gel for their high-efficiency single-chirality separation.

Chirality separation of mixed chiral microswimmers in a periodic channel

We numerically studied the dynamics and separation of mixed chiral microswimmers in a channel with regular arrays of rigid half-circle obstacles. Mixed chiral microswimmers can be separated by applying the shear flow or the constant load.