Collisionless Dynamo

Electron inertia is shown to dramatically impact the generation of a magnetic field by a flowing collisionless plasma. The rate at which magnetic field energy is created by the flow remains large as the magnetic Reynolds number $R_m\to \infty$, for both chaotic and nonchaotic flows. Importantly, a continuous nonchaotic laminar flow generates a magnetic field in a collisionless (zero collisional diffusion) plasma because of electron inertia. The magnetic field generated lies in a series of flux bundles with a scale size given by the collisionless electron skin depth.