Unique Electronic States in Non-centrosymmetric Cubic Compounds

We succeeded in growing single crystals of \(\hbox {Yb}_{4}\hbox {Sb}_{3}\), Ullmannite(NiSbS)-type compounds, \(\hbox {Pd}_{3}\hbox {Bi}_{2}\hbox {Si}_{2}\), EuPtSi, and EuPtGe with the non-centrosymmetric cubic structures by the Bridgman method. Split Fermi surface properties are clarified for \(\hbox {Yb}_{4}\hbox {Sb}_{3}\) and \(\hbox {Pd}_{3}\hbox {Bi}_{2}\hbox {Si}_{2}\). As for EuPtSi and EuPtGe with the cubic chiral structure, we observed the first-order like antiferromagnetic ordering at the Neel temperatures \(T_N=4.0\,{\rm K}\) and 3.4 K, respectively, which are small in magnitude compared with ordering temperatures of 10–100 K in the usual divalent Eu compounds, reflecting the frustration of spins in the chiral structure.