Feilian Zhang

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1. Introduction As of the end of June 2024, the number of construction enterprises engaged in construction activities in China had reached nearly 152,000, representing a year-on-year growth of 8.7%. The construction industry workforce has grown to 38.2 million people [1]. As the cornerstone of urban development, the construction workforce continues to expand, further highlighting the industry’s contribution to the national economy.

Broadband and weak-dispersion nonlinear response enhancement in the epsilon-near-zero region of a nano-stepped metasurface Optical media with dispersion-free large nonlinearity are highly desired for a broad range of applications, such as spectroscopy, all-optical data processing, and quantum information.