We show that electron interaction with the crystal lattice imposes stringent
symmetry constrains on the orbital moment propagation. We present examples that
elucidate the underlying mechanisms and reveal an additional effect of
ultrafast orbital moment oscillations not captured by the semiclassical models.
The constraints revealed by our analysis warrant re-interpretation of prior
observations, and suggest routes for efficient orbitronic device
implementation.Comment: 4.2 pages, 2 figure