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Abstract How a Mott insulator develops into a weakly coupled metal upon doping is a central question to understanding various emergent correlated phenomena. To analyze this evolution and its connection to the high-Tccuprates, we study the single-particle spectrum for the doped Hubbard model using cluster perturbation theory on superclusters. Starting from extremely low doping, we identify a heavily renormalized quasiparticle dispersion that immediately develops across the Fermi level, and a weakening polaronic side band at higher binding energy. The quasiparticle spectral weight roughly grows at twice the rate of doping in the low doping regime, but this rate is halved at optimal doping. In the heavily doped regime, we find both strong electron-hole asymmetry and a persistent presence of Mott spectral features. Finally, we discuss the applicability of the single-band Hubbard model to describe the evolution of nodal spectra measured by angle-resolved photoemission spectroscopy (ARPES) on the single-layer cuprate La2−xSrxCuO4(0 ≤x≤ 0.15). This work benchmarks the predictive power of the Hubbard model for electronic properties of high-Tccuprates.
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Electron‐Doping Mottronics in Strongly Correlated Perovskite
Abstract The discovery of hydrogen‐induced electron localization and highly insulating states in d‐band electron correlated perovskites has opened a new paradigm for exploring novel electronic phases of condensed matters and applications in emerging field‐controlled electronic devices (e.g., Mottronics). Although a significant understanding of doping‐tuned transport properties of single crystalline correlated materials exists, it has remained unclear how doping‐controlled transport properties behave in the presence of planar defects. The discovery of an unexpected high‐concentration doping effect in defective regions is reported for correlated nickelates. It enables electronic conductance by tuning the Fermi‐level in Mott–Hubbard band and shaping the lower Hubbard band state into a partially filled configuration. Interface engineering and grain boundary designs are performed for HxSmNiO3/SrRuO3heterostructures, and a Mottronic device is achieved. The interfacial aggregation of hydrogen is controlled and quantified to establish its correlation with the electrical transport properties. The chemical bonding between the incorporated hydrogen with defective SmNiO3is further analyzed by the positron annihilation spectroscopy. The present work unveils new materials physics in correlated materials and suggests novel doping strategies for developing Mottronic and iontronic devices via hydrogen‐doping‐controlled orbital occupancy in perovskite heterostructures.
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- Award ID(s):
- 1706815
- PAR ID:
- 10458693
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 32
- Issue:
- 6
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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