Local density of states study of a spin-orbit-coupling induced Mott insulatorSr2IrO4
| Autor: | Eduardo Calleja, Jixia Dai, Gang Cao, Kyle McElroy |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Condensed Matter::Quantum Gases
Physics Local density of states Condensed matter physics Band gap Mott insulator Fermi level 02 engineering and technology Spin–orbit interaction 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Electronic Optical and Magnetic Materials Mott transition symbols.namesake 0103 physical sciences symbols Condensed Matter::Strongly Correlated Electrons Strongly correlated material Metal–insulator transition 010306 general physics 0210 nano-technology |
| Zdroj: | Physical Review B. 90 |
| ISSN: | 1550-235X 1098-0121 |
| Popis: | We present scanning tunneling microscopy and spectroscopy experiments on the novel ${J}_{\mathrm{eff}}=1/2$ Mott insulator ${\mathrm{Sr}}_{2}\mathrm{Ir}{\mathrm{O}}_{4}$. Local density of states (LDOS) measurements show an intrinsic insulating gap of 620 meV that is asymmetric about the Fermi level and is larger than previously reported values. The size of this gap suggests that ${\mathrm{Sr}}_{2}\mathrm{Ir}{\mathrm{O}}_{4}$ is likely a Mott rather than Slater insulator. In addition, we found a small number of native defects which create in-gap spectral weight. Atomically resolved LDOS measurements on and off the defects show that this energy gap is quite fragile. Together the extended nature of the 5$d$ electrons and poor screening of defects help explain the elusive nature of this gap. |
| Databáze: | OpenAIRE |
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