Laser printing of resonant plasmonic nanovoids.
Hollow reduced-symmetry resonant plasmonic nanostructures possess pronounced tunable optical resonances in the UV-vis-IR range, being a promising platform for advanced nanophotonic devices. However, the present fabrication approaches require several consecutive technological steps to produce such nanostructures, making their large-scale fabrication rather time-consuming and expensive. Here, we report on direct single-step fabrication of large-scale arrays of hollow parabolic- and cone-shaped nanovoids in silver and gold thin films, using single-pulse femtosecond nanoablation at high repetition rates. The lateral and vertical size of such nanovoids was found to be laser energy-tunable. Resonant light scattering from individual nanovoids was observed in the visible spectral range, using dark-field confocal microspectroscopy, with the size-dependent resonant peak positions. These colored geometric resonances in far-field scattering were related to excitation and interference of transverse surface plasmon modes in nanovoid shells. Plasmon-mediated electromagnetic field enhancement near the nanovoids was evaluated via finite-difference time-domain calculations for their model shapes simulated by three-dimensional molecular dynamics, and experimentally verified by means of photoluminescence microscopy and Raman spectroscopy.
School of Natural Sciences, Far Eastern Federal University, 8 Sukhanova str., Vladivostok 690041, Russia. alex.iacp.dvo@mail.ru and Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Science, Vladivostok 690041, Russia.
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Kuchmizhak
School of Natural Sciences, Far Eastern Federal University, 8 Sukhanova str., Vladivostok 690041, Russia. alex.iacp.dvo@mail.ru and Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Science, Vladivostok 690041, Russia.
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Vitrik
Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Science, Vladivostok 690041, Russia.
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Kulchin
Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Science, Vladivostok 690041, Russia.
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Storozhenko
Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Science, Vladivostok 690041, Russia.
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Mayor
Institute of Chemistry, Far Eastern Branch, Russian Academy of Science, Vladivostok, 690022, Russia.
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Mirochnik
ITMO University, St Petersburg 197101, Russia.
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Makarov
ITMO University, St Petersburg 197101, Russia.
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Milichko
ITMO University, St Petersburg 197101, Russia and Lebedev Physical Institute, Russian Academy of Science, Moscow 119991, Russia.
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Kudryashov
Dukhov Research Institute of Automatics (SC Rosatom), 127055 Moscow, Russian Federation.
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Zhakhovsky
Dukhov Research Institute of Automatics (SC Rosatom), 127055 Moscow, Russian Federation and Landau Institute for Theoretical Physics, Russian Academy of Sciences, Chernogolovka, Russian Federation.
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Inogamov