Temperature dependent photoemission spectroscopy on lightly-doped sodium tungsten bronze

Temperature dependent photoemission studies on lightly doped ( x = 0.025 ) sodium tungsten bronzes, NaxWO3 have been investigated by high-resolution photoemission spectroscopy. The experimental results show evidence for polaron formation at the valence band edge and the photoemission spectra taken in different modes of the electron analyzer suggest that the density of states at the valence band edge gradually moves to other k -points in the Brillouin zone with increasing temperature and explain the dynamics of polarons in the insulating disordered sodium tungsten bronzes.