ABSENCE OF QUASI-PARTICLES IN THE PHOTOEMISSION SPECTRA OF QUASI-ONE-DIMENSIONAL BECHGAARD SALTS

We measured typical quasi-one-dimensional organic metals (Bechgaard sa lts), using high resolution angle-resolved photoemission spectroscopy. We observe neither quasiparticle features near the chemical potential nor traces of a Fermi surface. The spectra, indicating a deep pseudog ap around the Fermi energy, are incompatible with a Fermi liquid pictu re. None of the alternative interpretations we explored can fully expl ain the experimental data.