Splitting fermi surfaces and heavy electronic states in non-centrosymmetric U₃Ni₃Sn₄

We report the single-crystal growth of the non-centrosymmetric paramagnet U₃Ni₃Sn₄ by the Bridgman method and the Fermi surface properties detected by de Haas–van Alphen (dHvA) experiments. We have also investigated single-crystal U₃Ni₃Sn₄ by single-crystal X-ray diffraction, magnetization, electrical resistivity, and heat capacity measurements. The angular dependence of the dHvA frequencies reveals many closed Fermi surfaces, which are nearly spherical in topology. The experimental results are in good agreement with local density approximation (LDA) band structure calculations based on the 5 f-itinerant model. The band structure calculation predicts many Fermi surfaces, mostly with spherical shape, derived from 12 bands crossing the Fermi energy. To our knowledge, the splitting of Fermi surfaces due to the non-centrosymmetric crystal in 5 f-electron systems is experimentally detected for the first time. The temperature dependence of the dHvA amplitude reveals a large cyclotron effective mass of up to 35 m₀, indicating the heavy electronic state of U₃Ni₃Sn₄ due to the proximity of the quantum critical point. From the field dependence of the dHvA amplitude, a mean free path of conduction electrons of up to 1950 Å is detected, reflecting the good quality of the grown crystal. The small splitting energy related to the antisymmetric spin–orbit interaction is most likely due to the large cyclotron effective mass.