Peng Jun, Brandt Julia, Pfeiffer Maurice, G Maragno Laura, Krekeler Tobias, T James Nithin, Henf Julius, Heyn Christian, Ritter Martin, Eich Manfred, Petrov Alexander Yu, P Furlan Kaline, Blick Robert H, Zierold Robert
Center for Hybrid Nanostructures, Universität Hamburg, Luruper Chaussee 149, 22607 Hamburg, Germany.
Institute of Optical and Electronic Materials, Hamburg University of Technology, 21073 Hamburg, Germany.
ACS Appl Mater Interfaces. 2024 Dec 11;16(49):67106-67115. doi: 10.1021/acsami.4c13789. Epub 2024 Dec 2.
Photonic crystals (PhCs) are optical structures characterized by the spatial modulation of the dielectric function, which results in the formation of a photonic band gap (PBG) in the frequency spectrum. This PBG blocks the propagation of light, enabling filtering, confinement, and manipulation of light. Most of the research in this field has concentrated on static PhCs, which have fixed structural and material parameters, leading to a constant PBG. However, the growing demand for adaptive photonic devices has led to an increased interest in switchable PhCs, where the PBG can be reversibly activated or shifted. Vanadium dioxide (VO) is particularly notable for its near-room-temperature insulator-to-metal transition (IMT), which is accompanied by significant changes in its optical properties. Here, we demonstrate a fabrication strategy for switchable three-dimensional (3D) PhCs, involving sacrificial templates and a VO atomic layer deposition (ALD) process in combination with an accurately controlled annealing procedure. The resulting VO inverse opal (IO) PhC achieves substantial control over PBG in the near-infrared (NIR) region. Specifically, the synthesized VO IO PhC exhibits PBGs near 1.49 and 1.03 μm in the dielectric and metallic states of the VO material, respectively, which can be reversibly switched by adjusting the external temperature. Furthermore, a temperature-dependent switch from a narrow-band NIR reflector to a broad-band absorber is revealed. This work highlights the potential of integrating VO into 3D templates in the development of switchable photonics with complex 3D structures, offering a promising avenue for the advancement of photonic devices with adaptable functionalities.
光子晶体（PhCs）是一种光学结构，其特征在于介电函数的空间调制，这导致在频谱中形成光子带隙（PBG）。这个光子带隙会阻止光的传播，从而实现光的滤波、限制和操控。该领域的大多数研究都集中在静态光子晶体上，它们具有固定的结构和材料参数，从而产生恒定的光子带隙。然而，对自适应光子器件不断增长的需求促使人们对可切换光子晶体越来越感兴趣，在这种晶体中光子带隙可以被可逆地激活或移动。二氧化钒（VO）因其接近室温的绝缘体 - 金属转变（IMT）而特别引人注目，这种转变伴随着其光学性质的显著变化。在这里，我们展示了一种用于可切换三维（3D）光子晶体的制造策略，该策略涉及牺牲模板以及VO原子层沉积（ALD）工艺，并结合精确控制的退火程序。由此得到的VO反蛋白石（IO）光子晶体在近红外（NIR）区域实现了对光子带隙的有效控制。具体而言，合成的VO IO光子晶体在VO材料的介电态和金属态下分别在1.49和1.03μm附近呈现光子带隙，通过调节外部温度可以使其可逆切换。此外，还揭示了从窄带近红外反射器到宽带吸收器的温度依赖性转变。这项工作突出了将VO集成到具有复杂3D结构的可切换光子学3D模板中的潜力，为开发具有自适应功能的光子器件提供了一条有前景的途径。
