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Updated: Aug 14, 2026

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Spectroscopic indications of polaronic carriers in the quasi-one-dimensional conductor (TaSe4)2I
L Perfetti1, H Berger, A Reginelli
1Institut de Physique Appliquée, Ecole Polytechnique Fédérale (EPFL), CH-1015 Lausanne, Switzerland.
Abstract:
Angle-resolved photoemission (ARPES) on the quasi-one-dimensional conductor (TaSe4)2I shows a hidden Fermi-surface crossing in its metallic state and the opening of a Peierls gap at low temperatures. The underlying quasiparticles have vanishing spectral weight and extremely short coherence lengths. They are interpreted as polarons in the strong-coupling adiabatic limit, and almost all their ARPES weight is incoherent. These observations suggest a scenario where the long-standing contradictions between ARPES and other experiments on Peierls materials could be resolved.
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