Harmonic susceptibilities of MgB2

Abstract

In-phase and out-of-phase components of higher-harmonic ac susceptibilities χ_n= χ_n' – iχ_n" (from n = 2 to n = 7) of a bulk MgB₂ sample were obtained as a function of temperature. Both even and odd harmonics were obtained even in the absence of an applied dc field. The even harmonic signals are in general smaller in magnitude and about 10% of odd harmonic signals. The in-phase and out-of-phase components of odd harmonic susceptibilities become smaller in magnitude with increasing degree of harmonics.