Fig. 4: Modelled dispersion and occupation.

Dispersion and occupation numbers of electrons in the d_xz (blue solid lines) and in the d_yz (green solid lines) orbital states plotted in momentum space along the k_x direction. The chemical potential is fixed to μ = 1.2. a Difference between the orbital dispersions and the chemical potential, ε_k,a − μ, calculated from Eqs. (5), (6). Since \({V}_{{{{\bf{k}}}}}^{t}\) vanishes along the k_x-axis the dispersions ε_k,a correspond in the absence of nematic fluctuations, i.e. g = 0, to two bands leading to the well-known hole- and electron-like Fermi surface sheets around (0, 0) and (π, 0). b Orbital occupation numbers (per spin direction) as a function of momentum along the k_x-axis in the g = 0 case and a finite small temperature k_BT = 0.02. Due to the absence of interactions, these expectation values correspond to Fermi functions. c Same quantities for g = 0.2. To highlight their momentum variations due to the nematic fluctuations, the occupation numbers are plotted between 0.9 and 1.03 for the d_xz orbital and between 0 and 0.1 for the d_yz orbital.