Drag suppression in anomalous chiral media

Understand

We study a heavy impurity moving longitudinal with the direction of an external magnetic field in an anomalous chiral medium.

• Such system would carry a non-dissipative current of chiral magnetic effect associated with the anomaly.
• We show, by generalizing Landau's criterion for superfluidity, that the "anomalous component" which gives rise to the anomalous transport will {\it not} contribute to the drag experienced by an impurity.
• We argue on a very general basis that those systems with a strong magnetic field would exhibit an interesting transport phenomenon -- the motion of the heavy impurity is frictionless, in analogy to the case of a superfluid.