Abstract
The two-dimensional (2D) kagome superconductor CsV3Sb5 has attracted much recent attention due to the coexistence of superconductivity, charge orders, topology and kagome physics, which manifest themselves as distinct electronic structures in both bulk and surface states of the material. An interesting next step is to manipulate the electronic states in this system. Here, we report angle-resolved photoemission spectroscopy (ARPES) evidence for a surface-induced orbitalselective band reconstruction in CsV3Sb5. A significant energy shift of the electron-like band around Γ and a moderate energy shift of the hole-like band around M are observed as a function of time. This evolution is reproduced in a much shorter time scale by in-situ annealing of the CsV3Sb5 sample. Orbital-resolved density functional theory (DFT) calculations reveal that the momentum-dependent band reconstruction is associated with different orbitals for the bands around Γ and M, and the time-dependent evolution points to the change of sample surface that is likely caused by the formation of Cs vacancies on the surface. Our results indicate the possibility of orbital-selective control of the band structure via surface modification, which may open a new avenue for manipulating exotic phenomena in this material system, including superconductivity.
Original language | English |
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Article number | 057403 |
Journal | Chinese Physics B |
Volume | 31 |
Issue number | 5 |
DOIs | |
State | Published - May 2022 |
Externally published | Yes |
Funding
We thank useful discussions with X. H. Chen, T. Wu, Z. Y. Wang, J. J. Ying, Z. J. Xiang and K. Jiang. The work at University of Science and Technology of China (USTC) was supported by the Fundamental Research Funds for the Central Universities (Grant Nos. WK3510000008 and WK3510000012) and USTC start-up fund. Work at UC Santa Barbara was supported by the UC Santa Barbara NSF Quantum Foundry funded via the Q-AMASE-i program under award DMR-1906325. This research made use of the shared facilities of the NSF Materials Research Science and Engineering Center at UC Santa Barbara (DMR-1720256). B. R. O. acknowledges support from the California NanoSystems Institute through the Elings Fellowship program. S.M.L.T has been supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE-1650114.
Keywords
- band structure
- kagome superconductor
- photoemission