Abstract Van der Waals heterostructures are composed of stacked atomically thin two-dimensional (2D) crystals to provide unprecedented functionalities and novel physics. Franckeite, a naturally occurring van der Waals heterostructure consisting of superimposed SnS2-like and PbS-like layers alternately, shows intriguing potential in versatile optoelectronic applications. Here, we have prepared the few-layer franckeite via liquid-phase exfoliation method and characterized its third-order nonlinearity and ultrafast dynamics experimentally. We have found that the layered franckeite shows low saturable intensity, large modulation depth and picosecond ultrafast response. We have designed the passive photonic diodes based on the layered franckeite/C60 cascaded film and suspension configuration and found that the passive photonic diodes exhibit stable nonreciprocal transmission of light. The experimental results show the excellent nonlinear optical performance and ultrafast response of the layered franckeite, which may make inroad for the cost effective and reliable high-performance optoelectronic devices.

中文翻译：

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基于自然范德华异质结构的无源光子二极管

摘要范德华异质结构由堆叠的原子级薄二维 (2D) 晶体组成，以提供前所未有的功能和新颖的物理特性。Franckeite 是一种天然存在的范德华异质结构，由交替叠加的类 SnS2 和类 PbS 层组成，在多功能光电应用中显示出迷人的潜力。在这里，我们通过液相剥离法制备了几层方铅矿，并通过实验表征了其三阶非线性和超快动力学。我们发现层状方铅矿显示出低饱和强度、大调制深度和皮秒超快响应。我们已经设计了基于层状 franckeite/C60 级联薄膜和悬浮结构的无源光子二极管，并发现无源光子二极管表现出稳定的非互易光传输。实验结果表明层状方铅矿具有优异的非线性光学性能和超快响应，这可能有助于开发具有成本效益和可靠性的高性能光电器件。