In physics, the plasmaron was proposed by Lundqvist in 1967 as a quasiparticle arising in a system that has strong plasmon-electron interactions.
[1][2] In the original work, the plasmaron was proposed to describe a secondary peak (or satellite) in the photoemission spectral function of the electron gas.
The same authors pointed out, in a subsequent work, that this extra solution might be an artifact of the used approximations:[3] We want to stress again that the discussion we have given of the one-electron spectrum is based on the assumption that vertex corrections are small.
[9] However subsequent works discussed that the theoretical interpretation of the experimental measure was not correct,[10] in agreement with the fact that the plasmaron is only an artifact of the GW self-energy used with the Dyson equation.
The artificial nature of the plasmaron peak was also proven via the comparison of experimental and numerical simulations for the photo-emission spectrum of bulk silicon.