D. L. Feng

Bilayer Splitting in the Electronic Structure of Heavily Overdoped Bi2Sr2CaCu2O8 + delta

The electronic structure of heavily overdoped Bi(2)Sr(2)CaCu(2)O(8+delta) is investigated by angle-resolved photoemission spectroscopy. The long-sought bilayer band splitting in this two-plane system is observed in both normal and superconducting states, which qualitatively agrees with the bilayer Hubbard model calculations. The maximum bilayer energy splitting is about 88 meV for the normal state feature, while it is only about 20 meV for the superconducting peak.

Measurement of an Enhanced Superconducting Phase and a Pronounced Anisotropy of the Energy Gap of a Strained FeSe Single Layer in FeSe/Nb:SrTiO3/KTaO3 Heterostructures Using Photoemission Spectroscopy

R. Peng, 1, 2 X. P. Shen, 1, 2 X. Xie,1, 2 H. C. Xu,1, 2 S. Y. Tan, 1, 2 M. Xia,1, 2 T. Zhang, 1, 2 H. Y. Cao,1, 3 X. G. Gong, 1,3 J. P. Hu, 4, 5 B. P. Xie,1, 2,∗ and D. L. Feng1, 2,† 1State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai 200433, China 2Advanced Materials Laboratory, Fudan University, Shanghai 200433, People’s Republic of China 3 Key Laboratory for Computational Physical Sciences (MOE), Fudan University, Shanghai 200433, China 4Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, People’s Republic of China 5Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA (Dated: October 14, 2013)

Orbital characters of bands in the iron-based superconductor BaFe1.85Co0.15As2

The unconventional superconductivity in the newly discovered iron-based superconductors is intimately related to its multiband/multiorbital nature. Here we report the comprehensive orbital characters of the low-energy three-dimensional electronic structure in BaFe1.85Co0.15As2 by studying the polarization and photon-energy dependence of angle-resolved photoemission data. While the distributions of the dxz, dyz ,a ndd3z2−r2 orbitals agree with the prediction of density functional theory, those of the dxy and dx2−y2 orbitals show remarkable disagreement with theory. Our results point out the inadequacy of the existing band structure calculations and, more importantly, provide a foundation for constructing the correct microscopic model of iron pnictides.

Novel Mechanism of a Charge Density Wave in a Transition Metal Dichalcogenide

The charge density wave (CDW) is usually associated with Fermi surfaces nesting. We here report a new CDW mechanism discovered in a 2H-structured transition metal dichalcogenide, where the two essential ingredients of the CDW are realized in very anomalous ways due to the strong-coupling nature of the electronic structure. Namely, the CDW gap is only partially open, and charge density wave vector match is fulfilled through participation of states of the large Fermi patch, while the straight Fermi surface sections have secondary or negligible contributions.

Surface electronic structure and isotropic superconducting gap in ( Li 0.8 Fe 0.2 ) OH Fe Se

Using angle-resolved photoemission spectroscopy (ARPES), we revealed the surface electronic structure and superconducting gap of (Li

Evolution of the electronic structure of 1T-Cu(x)TiSe(2).

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Presence of exotic electronic surface states in LaBi and LaSb

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Electronic structure of single-crystalline NdO 0.5 F 0.5 BiS 2 studied by angle-resolved photoemission spectroscopy

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Superconducting coherence peak in the electronic excitations of a single-layer Bi2Sr1.6La0.4CuO6+delta cuprate superconductor.

)OHFeSe, an intercalated FeSe-derived superconductor without antiferromagnetic phase or Fe-vacancy order in the FeSe layers, and with a superconducting transition temperature (

Highly Anisotropic and Twofold Symmetric Superconducting Gap in Nematically OrderedFeSe0.93S0.07

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