Bulk Physical Properties of a Magnetic Weyl Semimetal Candidate NdAlGe Grown by a Laser Floating-Zone Method

We report the successful growth of single crystals of a magnetic Weyl semimetal candidate NdAlGe with the space group I41md. The crystals were grown by a floating-zone technique using five laser-diodes with the total power of 2 kW as the heat source. To ensure that the molten zone was stably formed during the growth, we employed a “bell shaped” distribution profile of the vertical irradiation intensity [Y. Kaneko and Y. Tokura, J. Crystal Growth 2020, 533, 125435]. Af-ter the nominal powder crushed from an arc-melted ingot was shaped under hydrostatic pres-sure, we sintered the feed and seed rods in an Ar atmosphere under ultra-low oxygen partial pressure (< 10^-26 atm) generated by an oxygen pump made of yttria-stabilized zirconia heated at 873 K. Single crystals of NdAlGe were successfully grown to a length of 50 mm. The grown crys-tals showed magnetic order in bulk at 13.5 K. The fundamental physical properties were charac-terized by magnetic susceptibility, magnetization, specific heat, thermal expansion, and electrical resistivity measurements. We demonstrate that the magnetic order induces anisotropic magneto-elasticity, magneto-entropy, and charge transport in NdAlGe.