De Haas-van Alphen effect and Fermi surfaces in UC

We grew a high-quality single crystal of UC and carried out the de Haas-van Alphen (dHvA) experiments. The Fermi surfaces of a semimetal UC were confirmed to consist of three ellipsoidal hole-Fermi surfaces centered at the X points and six cushion-like electron-Fermi surfaces centered at the W points in the FCC Brillouin zone. These Fermi surface properties are clarified on the basis of the combined results of dHvA experiments and SRAPW-energy band calculations. The hole and electron Fermi surfaces mainly originate from the C-2p valence band and the U-5f conduction band, respectively. The cyclotron mass of the hole is light, being a rest mass of an electron m₀, while the mass of the electron is heavy, being in the range from 4.0 to 15m₀. The mass enhancement is large for the electron Fermi surface, originated from the U-5f character.