Figure 1
(a) First-principles band calculations of FSs for x = 0.00. (b) FS mapping at x = 0.61 by hν = 40.8 eV. aT represents the inplane lattice parameter of the tetragonal structure. (c,d) E-k image and its second E derivative image for x = 0.61 along (0,0) – (π,π) direction. Two electron bands crossing EF around (π,π) is not separately detected in this experimental condition. (e1–k1) E-k images at the BZ corner on twinned crystals of 0.00 ≤ x ≤ 0.74. (e2–k2) The second E derivative E-k images of 0.00 ≤ x ≤ 0.74. (e3–k3) Schematic band dispersions obtained from (e2) to (k2). Blue and red curves correspond to the band dispersions of yz and xz orbitals, respectively. Broken curve in (e3) shows the degenerate xz/yz band at higher T.
