Kosters Dolfine, de Hoogh Anouk, Zeijlemaker Hans, Acar Hakkı, Rotenberg Nir, Kuipers L
Kavli Institute of Nanoscience, Department for Quantum Nanoscience, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
Center for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.
ACS Photonics. 2017 Jul 19;4(7):1858-1863. doi: 10.1021/acsphotonics.7b00496. Epub 2017 Jun 13.
We introduce core-shell plasmonic nanohelices, highly tunable structures that have a different response in the visible for circularly polarized light of opposite handedness. The glass core of the helices is fabricated using electron beam induced deposition and the pure gold shell is subsequently sputter coated. Optical measurements allow us to explore the chiral nature of the nanohelices, where differences in the response to circularly polarized light of opposite handedness result in a dissymmetry factor of 0.86, more than twice of what has been previously reported. Both experiments and subsequent numerical simulations demonstrate the extreme tunability of the core-shell structures, where nanometer changes to the geometry can lead to drastic changes of the optical responses. This tunability, combined with the large differential transmission, make core-shell plasmonic nanohelices a powerful nanophotonic tool for, for example, (bio)sensing applications.
我们引入了核壳等离子体纳米螺旋结构，这是一种高度可调谐的结构，对于相反旋向的圆偏振光在可见光范围内具有不同的响应。螺旋结构的玻璃核通过电子束诱导沉积制备，随后溅射涂覆纯金壳。光学测量使我们能够探究纳米螺旋的手性本质，其中对相反旋向圆偏振光的响应差异导致不对称因子为0.86，是先前报道值的两倍多。实验和随后的数值模拟均表明核壳结构具有极高的可调谐性，其中几何结构的纳米级变化可导致光学响应的剧烈变化。这种可调谐性与大的差分透射相结合，使核壳等离子体纳米螺旋成为一种强大的纳米光子工具，例如可用于（生物）传感应用。
