Charge carrier carriers by leaving behind holes (electrons) in the other band. In other words, charge carriers are particles/electrons that are free to move (carry the charge). They get charged at the battery/cell, and then flow throughout the circuit, giving energy to any components in the way, then when out of charge and towards the end of the circuit, they get re-charged by the battery/cell. Charge carrier In physics, a charge carrier is a particle or quasiparticle that is free to move, carrying an electric charge, especially the particles that carry electric charges in electrical conductors. Examples are electrons, ions and holes.
Charge radius customary when charge radius takes an imaginary numbered value to report the negative valued square of the charge radius, rather than the charge radius itself, for a particle. The best known particle with a negative squared charge radius is the neutron. The heuristic explanation for why the squared charge radius of a neutron is negative, despite its overall neutral electric charge, is that this is the case because its negatively charged down quarks are, on average, located in the outer part of the neutron, while its positively charged up quark is, on average, located towards the center of the neutron.