Spectral weight transfer in multiorbital Mott systems

We develop here a general formalism for multiorbital Mott systems that can be used to understand dynamical and static spectral weight transfer. We find that the spectral weight transferred from the high-energy scales is greatly increased as a result of the multiorbital structure. As a consequence certainly dynamically generated symmetries are obtained at lower values of doping than in the single-band Hubbard model. For example, in the atomic limit for filling less than one electron per site, the particle-hole symmetric condition in the lower band shifts from the one-band result of x=1/3 to x=1/(2n_o+1), where n_o is the number of orbitals with an unpaired spin. Transport properties computed from effective low-energy theories that forbid double occupancy of bare electrons, such as the multiorbital t-J generalization, should all be be sensitive to this particle-hole symmetric condition. Away from the atomic limit, the dynamical contributions increase the transferred spectral weight. Consequently, any phenomena that are sensitive to an emergent particle-hole symmetry should be obtained at x<[1/(2n_o+1)].