Superconductivity in a new ternary compound of the Ta-Zr-B system with FeB prototype structure*

Recently was published the discovery of superconductivity in Ta$_{\mathrm{1-x}}$Hf$_{\mathrm{x}}$B which presents maximum T$_{\mathrm{c}}$ close to 6.7 K on the Ta$_{\mathrm{0.7}}$Hf$_{\mathrm{0.3}}$B nominal composition. This material display strongly signature of a new multiband compound. Within this scenario in this work we shall show a systematic study in the Ta$_{\mathrm{1-x}}$Zr$_{\mathrm{x}}$B series of the compounds. The results sustained by X-ray diffraction, resistivity, magnetization and heat capacity measurements suggest that all series crystallize in FeB prototype structure with maximum superconducting critical temperature close to 6.0 K for Ta$_{\mathrm{0.8}}$Zr$_{\mathrm{0.2}}$B nominal composition.