近日，美国伊利诺伊大学厄巴纳-香槟分校的Kejie Fang及其研究团队取得一项新进展。经过不懈努力，他们实现了用于宽带、超高效非线性转换及纠缠光子产生的InGaP χ⁽²⁾集成光子平台。相关研究成果已于2024年10月15日在国际知名学术期刊《光：科学与应用》上发表。

本文展示了一种用于宽带、超高效二阶非线性光学的铟镓磷化物（InGaP）集成光子平台。该InGaP纳米光子波导在1.55微米泵浦波长下实现了归一化效率为128,000%/W/cm²的二次谐波产生，比电信C波段的现有技术水平高出近两个数量级。

此外，研究人员还实现了一个超亮、宽带的时间-能量纠缠光子源，其成对产生率为97 GHz/mW，带宽为115纳米，中心位于电信C波段。该InGaP纠缠光子源展现出高符合-偶然计数比（CAR > 10⁴）和双光子干涉可见度（> 98%）。InGaP二阶非线性光子平台将对非经典光产生、光信号处理和量子网络产生广泛影响。

据悉，非线性光学在科学与技术的众多领域中扮演着重要角色。非线性光学的发展得益于，具有不断增强光学非线性特性的材料的发现与应用。

附：英文原文

Title: InGaP χ⁽²⁾ integrated photonics platform for broadband, ultra-efficient nonlinear conversion and entangled photon generation

Author: Akin, Joshua, Zhao, Yunlei, Misra, Yuvraj, Haque, A. K. M. Naziul, Fang, Kejie

Issue&Volume: 2024-10-15

Abstract: Nonlinear optics plays an important role in many areas of science and technology. The advance of nonlinear optics is empowered by the discovery and utilization of materials with growing optical nonlinearity. Here we demonstrate an indium gallium phosphide (InGaP) integrated photonics platform for broadband, ultra-efficient second-order nonlinear optics. The InGaP nanophotonic waveguide enables second-harmonic generation with a normalized efficiency of 128, 000%/W/cm² at 1.55 μm pump wavelength, nearly two orders of magnitude higher than the state of the art in the telecommunication C band. Further, we realize an ultra-bright, broadband time-energy entangled photon source with a pair generation rate of 97 GHz/mW and a bandwidth of 115 nm centered at the telecommunication C band. The InGaP entangled photon source shows high coincidence-to-accidental counts ratio CAR > 10⁴ and two-photon interference visibility > 98%. The InGaP second-order nonlinear photonics platform will have wide-ranging implications for non-classical light generation, optical signal processing, and quantum networking.

DOI: 10.1038/s41377-024-01653-5

Source: https://www.nature.com/articles/s41377-024-01653-5