529 citations · 530 across the 7 of their papers we have counts for
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Why polar excitons stay sharp: parity protection of the center-of-mass recoil channel in exciton-phonon scattering
Michael O. Atambo
In polar semiconductors the Fröhlich interaction is the dominant electron--phonon coupling, yet excitonic resonances in materials such as halide perovskites remain anomalously shar…
Mass-asymmetry-controlled exciton dressing and dissociation in a quantum lattice model
Michael O. Atambo
In a polar material, a neutral exciton couples to phonons through the sum of the electron and hole deformation potentials. Because the total source vanishes by charge neutrality, t…
Splicing an exact local self-energy into : tests on small Hubbard clusters
Michael O. Atambo
+DMFT-type schemes replace the local part of a self-energy by a separately computed local self-energy. A causal double counting removes a non-causal term from the hybridiz…
Accidental accuracy and formal consistency in +BSE: Exact benchmarks and regime-dependent error cancellation
Michael O. Atambo
Standard many-body perturbation theory for optical excitations combines the approximation for quasiparticle energies with the Bethe-Salpeter equation (BSE) for the electron-ho…
Parity-selected Bethe-Salpeter equation: symmetry-adapted regularization of the exciton-phonon self-energy in polar semiconductors
Michael O. Atambo
Finite-temperature Bethe-Salpeter calculations of exciton-phonon self-energies in polar materials are bottlenecked by the Fröhlich divergence of the intra-1s scattering vertex. We…
Parity-controlled electron-hole interference in exciton-phonon coupling
Michael O. Atambo
We demonstrate that exciton-phonon coupling in polar semiconductors is governed by a parity-controlled interference selection rule. By performing an exact multipole expansion of th…
Exact benchmarks for the plasmon-pole approximation: Multi-scale screening and the breakdown of the quasiparticle picture
Michael O. Atambo
The approximation is the gold standard for calculating quasiparticle band structures, yet its computational cost frequently necessitates the use of the plasmon-pole approximat…
Symmetry-protected intraband exciton-phonon scattering and its breakdown by mass asymmetry
Michael O. Atambo
The coupling of excitons to lattice vibrations is typically treated via phenomenological models that artificially separate long-range Fröhlich and short-range Holstein interactions…
Accidental accuracy and vertex corrections in : Exact benchmarks for the extended Hubbard model
Michael O. Atambo
The approximation is the standard tool for quasiparticle predictions in materials, yet its regime of validity in correlated systems remains poorly quantified, because \textit{…
Unraveling the effects of anionic vacancies and temperature on mechanical properties of NbC and NbN: Insights from Quantum Mechanical Study
P. W. Muchiri, K. K. Korir, N. W. Makau +2
Transition metal carbides and nitrides (TMCNs), such as niobium carbide (NbC) and niobium nitride (NbN), are of great technological interest due to their exceptional hardness, high…