Single-crystal growth of the Weyl semimetals candidates PrAlGe and CeAlGe

The theoretically predicted magnetic Weyl semimetals RAlGe (R = Pr, Ce) were grown in Paul Scherrer Institute using a HKZ floating zone furnace as well as Al self-flux growth. The authors around group leader Ekaterina Pomjakushina recently published the details on crystal growth and analysis. Only by the FZ approach truly stoichiometric single crystals could be obtained reliably, whereas the crystals grown by a flux-growth technique tend to be Al-rich. Magnetic characterization and transport data obtained from the single crystals confirm that the crystals have physical properties consistent with those expected for magnetic semimetals, although neither displays the theoretically expected ferromagnetic ground state.

The floating-zone technique with enhanced gas pressures of up to 30 bar once again turned out to be crucial to obtain high-quality single crystals. The grown crystals provide an ideal platform for neutron and photon scattering microscopic studies of the magnetic field-tunable correlation physics involving magnetism and topological Weyl nodes.