Reversible optical switching of highly confined phonon-polaritons with an ultrathin phase-change material
Reversible optical switching of highly confined phonon-polaritons with an ultrathin phase-change material
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DOI：
10.1038/nmat4649
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发表时间：
2016-08-01
期刊：
影响因子：
41.2
通讯作者：
Taubner, Thomas
中科院分区：
文献类型：
--
作者：
Li, Peining;Yang, Xiaosheng;Taubner, Thomas
表面声子极化激元（SPhPs），光子与声子耦合在极性晶体中的集体激发，使强大的光-物质相互作用和许多红外纳米光子应用。然而，由于晶格振动是由晶体结构决定的，因此SPhPs的动态控制仍然具有挑战性。在这里，我们实现了全光，非易失性，可逆开关的SPhPs通过控制的相变材料（PCM）的结构相作为一个可切换的介电环境。我们用单脉冲激光实验证明了一种可调谐的PCM薄膜的光开关（低至7 nm，<λ/1，200），并在石英中检测到超受限的SPhPs（极化子波矢量k（p）> 70 k（0），k（0）= 2 π/λ）。我们的概念证明允许制备全介质，全SPhP谐振器，而不需要复杂的制造方法。通过优化的材料和并行化的光学寻址，我们预见了可切换红外纳米光子元件的应用潜力，例如，成像元件，如超级透镜和超透镜，以及可重新配置的超表面和传感器。
Surface phonon-polaritons (SPhPs), collective excitations of photons coupled with phonons in polar crystals, enable strong light-matter interaction and numerous infrared nanophotonic applications. However, as the lattice vibrations are determined by the crystal structure, the dynamical control of SPhPs remains challenging. Here, we realize the all-optical, non-volatile, and reversible switching of SPhPs by controlling the structural phase of a phase-change material (PCM) employed as a switchable dielectric environment. We experimentally demonstrate optical switching of an ultrathin PCM film (down to 7 nm, < lambda/1,200) with single laser pulses and detect ultra-confined SPhPs (polariton wavevector k(p) > 70k(0), k(0) = 2 pi/lambda) in quartz. Our proof of concept allows the preparation of all-dielectric, rewritable SPhP resonators without the need for complex fabrication methods. With optimized materials and parallelized optical addressing we foresee application potential for switchable infrared nanophotonic elements, for example, imaging elements such as superlenses and hyperlenses, as well as reconfigurable metasurfaces and sensors.