Calculating critical temperatures of superconductivity from a renormalized Hamiltonian

摘要: It is shown that one can obtain quantitatively accurate values for the superconducting critical temperature within a Hamiltonian framework. This possible if uses renormalized contains an attractive electron-electron interaction and single-particle energies. be obtained by similarity renormalization or using flow equations Hamiltonians. We calculate as function of coupling standard BCS-theory. For small we rederive McMillan formula Tc. compare our results with Eliashberg theory experimental data from various materials. The theoretical agree 10%. Renormalization Hamiltonians provides promising way to investigate electron-phonon interactions in strongly correlated systems.