Fully Two-Dimensional Incommensurate Charge Modulation on the Pd-Terminated Polar Surface of PdCoO2
Pengfei Kong1, Guowei Li2,3,4, Zhongzheng Yang1
1School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
Nano Letters
|July 15, 2022
Summary
We discovered a novel 2D incommensurate charge modulation and moiré pattern on the palladium (Pd) surface of PdCoO2. This finding reveals new electronic properties of this material and its polar surfaces.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Surface Science
Background:
- Polar surfaces of transition metal oxides like PdCoO2 exhibit unique electronic properties.
- Understanding surface states is crucial for novel electronic applications.
Purpose of the Study:
- To investigate the electronic properties of the polar surfaces of PdCoO2 using advanced microscopy techniques.
- To identify and characterize surface-induced phenomena on both CoO2- and Pd-terminated surfaces.
Main Methods:
- Low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS).
- Analysis of quasiparticle interference patterns.
- Characterization of surface lattice structures and electronic modulations.
Main Results:
- Observed Rashba-like spin-split surface states on the CoO2-terminated surface.
- Identified a 2D incommensurate charge modulation on the Pd-terminated surface, driven by Fermi surface nesting.
- Discovered a moiré pattern resulting from the interference between the charge modulation and the atomic lattice.
Conclusions:
- PdCoO2 exhibits novel electronic phenomena on its polar surfaces, including incommensurate charge modulation and moiré patterns.
- These findings contribute to a deeper understanding of the electronic properties of PdCoO2.
- The study opens avenues for exploring new electronic functionalities in this material.
Keywords:
Fermi surface nestingPd-terminated polar surfaceincommensurate charge modulationmoiré superlatticescanning tunneling microscopyMore Related Videos
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