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arXiv · 2502.04255

The effect of Carrier Doping and Thickness on the Electronic Structures of La$3$Ni$2$O$7$ Thin Films

Haoliang Shi·Zihao Huo·Guanlin Li·Hao Ma·Tian Cui·Dao-Xin Yao·Defang Duan
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Abstract

Recently, the superconductivity of bilayer nickelate La3Ni2O7 has been observed in the thin film at ambient pressure, facilitated by epitaxial strain. Here, we investigate the effects of film thickness and carrier doping on the electronic structure of La3Ni2O7 thin films with thickness of 0.5-3 unit cells (UC) using first-principles calculations. At an optimal doping concentration of 0.4 holes per formula unit for 2UC film, the Ni-"d" _("z" ^"2" ) interlayer bonding state metallizes, leading to the formation of {\gamma} pockets at the Fermi surface, which quantitatively matches the experimental results of angle-resolved photoemission spectroscopy (ARPES). These findings provide theoretical support for recent experimental observations of ambient-pressure superconductivity in La3Ni2O7 thin films and highlight the crucial role of film thickness and carrier doping in modulating electronic properties.

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Haoliang Shi, Zihao Huo, Guanlin Li, Hao Ma, Tian Cui, Dao-Xin Yao, Defang Duan. 2025-02-06. The effect of Carrier Doping and Thickness on the Electronic Structures of La$3$Ni$2$O$7$ Thin Films. https://arxiv.org/abs/2502.04255

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