On the change of resistance of nickel in a magnetic field

Abstract

In a recent paper Gerlach and Schneiderhan have described a series of experiments on the resistance of nickel considered both as a function of the temperature and as a function of an external field applied parallel to the wire. In the absence of an external field the change of resistance with temperature can be considered as made up of two terms, the first being due to the result of the ordinary temperature coefficient of resistance, and the second (∆R) being proportional to the energy of spontaneous magnetisation. According to the Weiss theory this energy of spontaneous magnetisation is equal to ‒½ n σ 2 , where n is the constant of the intramolecular field and σ the volume intensity of magnetisation. Plotting ∆R against T, and σ 2 against T, Gerlach and Schneiderhan obtained curves which were coincident over the whole range from room temperature to the Curie point. The agreement is extra­ordinarily close and leaves no doubt as to the intimate connection between ∆R and σ 2 .