Open AccessElectronic properties of Ba 1 − x Sr x V 13 O 18 Author(s) -
S. Dash,
Mario Okawa,
T. Kajita,
T. Yoshino,
R. Shimoyama,
Kazutoshi Takahashi,
Y. Takahashi,
Ryohei Takayanagi,
T. Saitoh,
Daiki Ootsuki,
T. Yoshida,
Eiji Ikenaga,
N. L. Saini,
T. Katsufuji,
T. Mizokawa
Publication year - 2017
Publication title -
physical review. b./physical review. b
Language(s) - English
Resource type - Journals
eISSN - 2469-9969
pISSN - 2469-9950
DOI - 10.1103/physrevb.95.195116
Subject(s) - trimer , charge (physics) , order (exchange) , valence (chemistry) , photoemission spectroscopy , phase (matter) , physics , phase transition , crystallography , fermi level , materials science , analytical chemistry (journal) , condensed matter physics , x ray photoelectron spectroscopy , electron , chemistry , nuclear magnetic resonance , nuclear physics , dimer , finance , quantum mechanics , chromatography , economics
We have studied the electronic structure of Ba1−x Srx V13 O18 (x = 0,0.2,1) at different temperatures across the trimerization and charge-order transitions using hard x-ray photoemission spectroscopy (HAXPES). The V 2p HAXPES indicates V2+/V3+ charge order and fluctuation in the high-temperature tetramer phase, low- temperature trimer phase, and intermediate-temperature charge-order phase in the series of x = 0,0.2,1. In the valence-band HAXPES, although the spectral weight at the Fermi level tends to be suppressed in all the phases due to strong charge order or fluctuation, it increases in the trimer phase at x = 0.2, in agreement with the decrease of resistivity and the increase of itinerant electrons in the trimer phase. Interestingly, in the most conducting x = 1 without the charge-order phase, the spectral weight at the Fermi level is strongly suppressed even in the trimer phase, indicating that charge fluctuation in the trimer phase is different between x = 0.2 and 1