Fermi surface evolution and Luttinger theorem in Na(x)CoO2: a systematic photoemission study.
We report a systematic angle-resolved photoemission study on Na(x)CoO2 for a wide range of Na concentrations (0.3 < or = x < or = 0.72). In all the metallic samples at different x, we observed (i) only a single holelike Fermi surface centered around gamma and (ii) its area changes with x according to the Luttinger theorem. We also observed a surface state that exhibits a larger Fermi surface area. The e'(g) band and the associated small Fermi surface pockets near the K points predicted by band calculations are found to sink below the Fermi energy in a manner almost independent of the doping and temperature.
Yang
H-B
HB
Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467, USA.
Pan
Z-H
ZH
Sekharan
A K P
AK
Sato
T
T
Souma
S
S
Takahashi
T
T
Jin
R
R
Sales
B C
BC
Mandrus
D
D
Fedorov
A V
AV
Wang
Z
Z
Ding
H
H