研究目的
To study the evolution of the electronic structures of Bi2Sr2CaCu2O8+x using ozone/vacuum annealing technique together with tight binding fits and to extract the tight binding parameters to study their evolution with doping.
研究成果
The evolution of the electronic structure of Bi2212 within a nearly whole superconducting dome is presented by measuring on a continuously doped surface of Bi2212 using in-situ ARPES. The values of TB parameters and their evolution with doping are determined, which are important for theoretical modeling of high-Tc cuprates.
研究不足
The TB band does not match well with the measured bands along MY direction in the underdoped (UD) region, which might be related to some kind of exotic behaviors of this strange metal phase. The band dispersion along ΓY was measured in the superconducting state since the superconducting gap is zero along this direction.
1：Experimental Design and Method Selection:
The study uses a technique of ozone/vacuum annealing to continuously change the doping level of the surface of Bi2Sr2CaCu2O8+x and measures the electronic structures by in-situ angle-resolved photoemission spectroscopy (ARPES). Tight binding (TB) model is applied to fit the electronic structure obtained by this technique.
2：Sample Selection and Data Sources:
The surface treatments through ozone/vacuum annealing and the sample preparation are described in the paper. In-situ ARPES measurements were carried out on Bi2Sr2CaCu2O8+x.
3：List of Experimental Equipment and Materials:
ARPES system equipped with a Scienta R4000 analyzer and a Scienta VUV source. A He Iα resonant line (hυ=21.218 eV) was used.
4：218 eV) was used.
Experimental Procedures and Operational Workflow:
4. Experimental Procedures and Operational Workflow: The vacuum of the ARPES chamber was better than 3×10?11 torr. The energy and angular resolution was set at ~20 meV and 0.2°, respectively. All Fermi surface sheets were acquired at 30 K and integrated over ±10 meV around the Fermi energy.
5：2°, respectively. All Fermi surface sheets were acquired at 30 K and integrated over ±10 meV around the Fermi energy.
Data Analysis Methods:
5. Data Analysis Methods: The single-band TB model plus a bilayer splitting term is used to fit the FS sheets with the constraint t″/t′=?1/2. The TB parameters are extracted to study their evolution with doping.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
