Intrinsic diamagnetism in the Weyl semimetal TaAs

•TaAs crystals exhibit intrinsic diamagnetism.•A minimum in magnetization as a function of temperature is revealed.•The intrinsic properties of the Weyl nodes are concealed in bulk TaAs.•The samples are proposed to be as thin as possible to study the Weyl nodes.

We investigate the magnetic properties of TaAs, a prototype Weyl semimetal. TaAs crystals show diamagnetism with magnetic susceptibility of about −7×10−7 emu/(g Oe) at 5 K. A general feature is the appearance of a minimum at around 185 K in magnetization measurements as a function of temperature, which resembles that of graphite. No phase transition is observed in the temperature range between 5 K and 400 K.