Theoretical and experimental research on the second-order magnetic field

This article deals with the second-order magnetic field, which appears significant in inhomogeneous current systems, where the total electric current has a zero value. The origin of this field is affected by the different drift velocities of the charge carriers in the individual parts of the system. The field is of a relativistic nature. This work describes suitable current systems as the origins of this field. Their main component is a semiconductor or superconductor bar, or if need be a beam of accelerated charged particles (electrons). The induction of this field in direct and alternating systems is calculated. The most significant component of this field is the acceleration boundary field, which appears in the thin boundary layers between the conductors with different drift velocities. The electromagnetic induction method of measuring the alternating second-order magnetic field is described. The article also gives an account of a successful experiment, which has confirmed the existence of this field with fast electrons in both a qualitative and quantitative way. The work discusses the possibilities of realisation of the current system with the semiconductor or superconductor and their application in the research of transport phenomena.