Hallmarks of the Mott-metal crossover in the hole-doped pseudospin-1/2 Mott insulator Sr2IrO4.
The physics of doped Mott insulators remains controversial after decades of active research, hindered by the interplay among competing orders and fluctuations. It is thus highly desired to distinguish the intrinsic characters of the Mott-metal crossover from those of other origins. Here we investigate the evolution of electronic structure and dynamics of the hole-doped pseudospin-1/2 Mott insulator Sr2IrO4. The effective hole doping is achieved by replacing Ir with Rh atoms, with the chemical potential immediately jumping to or near the top of the lower Hubbard band. The doped iridates exhibit multiple iconic low-energy features previously observed in doped cuprates-pseudogaps, Fermi arcs and marginal-Fermi-liquid-like electronic scattering rates. We suggest these signatures are most likely an integral part of the material's proximity to the Mott state, rather than from many of the most claimed mechanisms, including preformed electron pairing, quantum criticality or density-wave formation.
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Yue
http://orcid.org/0000-0002-3989-158X
Y
Cao
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Qiang
Q
Wang
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Justin A
JA
Waugh
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Theodore J
TJ
Reber
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Haoxiang
H
Li
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Xiaoqing
X
Zhou
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Stephen
S
Parham
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.|Department of Physics, Incheon National University, Incheon 22012, Korea.
S-R
SR
Park
Swiss Light Source, Paul Scherrer Institut, Villigen PSI CH-5232, Switzerland.
Nicholas C
http://orcid.org/0000-0002-2334-8494
NC
Plumb
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Eli
E
Rotenberg
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Aaron
A
Bostwick
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Jonathan D
JD
Denlinger
Department of Physics and Astronomy, Center for Advanced Materials, University of Kentucky, Lexington, Kentucky 40506, USA.
Tongfei
T
Qi
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Michael A
MA
Hermele
Department of Physics and Astronomy, Center for Advanced Materials, University of Kentucky, Lexington, Kentucky 40506, USA.
Gang
G
Cao
Department of Physics, University of Colorado, Boulder, Colorado 80309, USA.
Daniel S
DS
Dessau