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arXiv · 2505.08289

Nonlinear optical response in kagome lattice with inversion symmetry breaking

Xiangyang Liu·Junwen Lai·Jie Zhan·Tianye Yu·Peitao Liu·Seiji Yunoki·Xing-Qiu Chen·Yan Sun
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Abstract

The kagome lattice is a fundamental model structure in condensed matter physics and materials science featuring symmetry-protected flat bands, saddle points, and Dirac points. This structure has emerged as an ideal platform for exploring various quantum physics. By combining effective model analysis and first-principles calculations, we propose that the synergy among inversion symmetry breaking, flat bands, and saddle point-related van Hove singularities within the kagome lattice holds significant potential for generating strong second-order nonlinear optical response. This property provides an inspiring insight into the practical application of the kagome-like materials, which is helpful for a comprehensive understanding of kagome lattice-related physics. Moreover, this work offers an alternative approach for designing materials with strong a second-order nonlinear optical response.

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Xiangyang Liu, Junwen Lai, Jie Zhan, Tianye Yu, Peitao Liu, Seiji Yunoki, Xing-Qiu Chen, Yan Sun. 2025-05-13. Nonlinear optical response in kagome lattice with inversion symmetry breaking. https://doi.org/10.1021/acsnano.4c17371

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