Self-energy corrections to theabinitioband structure: Chromium

Abstract

We describe the effect of many-particle corrections to improve the electronic energy spectrum calculated in the framework of the density functional formalism (DFF). We show that it is possible to consider an n-particle diagram like a correction to the DFF results for electronic structure, if we take into account the electron-electron interaction with nonzero transmitted momentum q or energy E. A model is proposed for calculating the leading term of the self-energy expansion as a power series in interactions, i.e. , the second-order term under the conditions q=0 and E&0. This model is illustrated by calculating the electronic band structure and optical properties of antiferromagnetic chromium.The self-energy correction leads to a better agreement between the theoretical calculations and experimental measurements of electronic properties.

First-Principles Theory of Ferromagnetic and Antiferromagnetic Order

“…Irrespective of the exchange±correlation potential we are using, the calculation yields an antiferroFirst-Principles Theory of Ferromagnetic and Antiferromagnetic Order magnetic ground state. This is in agreement with neutron scattering experiments by Bacon [93] and with calculations by Kulnikov et al [94] and Ku È bler et al [81] who obtain a magnetic moment of approximately 0.6m B per atom corroborating the experimental results. Calculations performed by Chen et al [95] and Skriver [96] for the experimental lattice constant yield also antiferromagnetic order, but the magnetic moments strongly deviate from the experimental value.…”

Ultrafast photoinduced shift of cavity modes in semiconductor microcavity under femtosecond excitations

“…The density of electron states in Cr sharply increases with increasing |E-E F | [8]. Thus one can expect Cr will be very effective injector of electrons and holes into ZnSe because the density of states at and above the energies of the Schottky electron barrier is very high.…”

Quantum Notions of Stress

“…The kinetic term kin ͑r͒, however, entails the knowledge of the one-particle density matrix ͑r , rЈ͒ which is a manybody term. Prescriptions to calculate the density matrix have been proposed by Hybertsen and Louie ͑1986, 1987͒, Godby et al ͑1986, 1987͒, and others ͑Horsch et al 1987Kulikov et al 1987;Mazin et al 1984͒. Experimental determination of ͑r , rЈ͒ is also possible.…”