Extraordinary Five-Wave Mixing in a Zinc Oxide Microwire on a Au Film.

Zhang, Tianzhu; Li, Haixia; Gao, Yihua; Shi, Zhifeng; Zhang, Shunping; Xu, Hongxing · Nano Lett · 2023

basic_science · Level V

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Abstract

Coherent multiwave mixing is in demand for optical frequency conversion, imaging, quantum information science, etc., but has rarely been demonstrated in solid-state systems. Here, we observed three- and five-wave mixing (5WM) in a <i>c</i>-axis growth zinc oxide microwire on a Au film with picosecond pulses in the near-infrared region. An output 5WM of 4.7 × 10<sup>-7</sup> μW, only 2-3 orders smaller than the three-wave mixing, is achieved when the excitation power is as low as 1.5 mW and the peak power density as weak as ∼10<sup>7</sup> W/cm<sup>2</sup>. The excitation power dependence of 5WM agrees well with the perturbation limit under the low intensity but exhibits a strong deviation at a high pumping power. This extraordinary behavior is attributed to the cooperative resonant enhancement effect when pumping in the near-infrared range. Our study offers a potential solid-state platform for on-chip multiwave mixing and quantum nonlinear optics, such as generating many-photon entangled states or the construction of photon-photon quantum logic gates.