Optical seminar | 28 May 2021
Metasurfaces composed of designed semiconductor nanoresonators arranged in a plane offer unique opportunities for controlling the properties of light fields . Such metasurfaces can e.g. impose a spatially variant phase shift onto an incident light field, thereby providing control over its wave front with high transmittance efficiency. However, most semiconductor metasurfaces realized so far were passive and linear, and their optical response was permanently encoded into the structure during fabrication. Recently, a growing amount of research is concentrating on active metasurfaces, specifically on the integration of emitters and optical nonlinearities into dielectric and semiconductor metasurfaces, and on obtaining dynamic control of their optical response [2,3].
This talk will provide an overview of our recent advances in nonlinear, tunable, and light-emitting all-dielectric metasurfaces.
In particular, we have studied spontaneous emission from metasurfaces incorporating various types of emitters, including semiconductor quantum dots , monolayers of transition metal dichalcogenides , and trivalent lanthanide ions exhibiting magnetic-dominated dipole transitions . Along similar lines, we have investigated second harmonic generation in metasurfaces made of, or containing, materials with a high second-order nonlinear susceptibility, such as III-V semiconductors , lithium niobate, and monolayers of transition metal dichalcogenides. Our results show that both the directional, spectral, and/or polarization properties of the spontaneously emitted or generated second harmonic light can be tailored by the metasurface design.
For dynamic tuning of the metasurface response, we make use of the strong spectral dispersion associated with the resonant optical response of the metasurfaces in combination with the sensitivity of the resonance properties on the refractive index of the dielectric environment or constituent material of the individual nanoresonators. Specifically, by integrating the semiconductor metasurfaces into nematic-liquid-crystal cells, we can dynamically tune their linear-optical response in the near-infrared spectral range using an applied voltage as control parameter . Using photoalignment materials, we furthermore show that this tuning approach can be extended to visible frequencies. Based on this approach, we experimentally realized a transparent metasurface display with high tuning contrast in the visible .
Our results illustrate the potential of all-dielectric metasurfaces for compact tunable and reconfigurable optical components and flat sources of tailored light fields.
 I. Staude and J. Schilling, “Metamaterial-inspired silicon nanophotonics”, Nature Photon. 11, 274 (2017).
 A. Vaskin, R. Kolkowski, A. F. Koenderink, and I. Staude, “Light-Emitting Metasurfaces“, Nanophotonics, 8, 1151-1198 (2019).
 C. Zou, J. Sautter, F. Setzpfandt, and I. Staude, „Resonant Dielectric Metasurfaces – Active Tuning and Nonlinear Effects”, J. Phys. D: Appl. Phys. 52, 373002 (2019).
 S. Liu, A. Vaskin, S. Addamane, B. Leung, M.-C. Tsai, Y. Yang, P. Vabishchevich, G. Keeler, G. Wang, X. He, Y. Kim, N. Hartmann, H. Htoon, S. Doorn, M. Zilk, T. Pertsch, G. Balakrishnan, M. Sinclair, I. Staude, and I. Brener, “Light Emitting Metasurfaces: simultaneous control of spontaneous emission and far-field radiation”, Nano Lett. 18, 6906 (2018).
 T. Bucher, A. Vaskin, R. Mupparapu, F. J. F. Löchner, A. George, K. E. Chong, S. Fasold, C. Neumann, D.-Y. Choi, F. Eilenberger, F. Setzpfandt, Y. S. Kivshar, T. Pertsch, A. Turchanin, and I. Staude, “Tailoring photoluminescence from MoS2 monolayers by Mie-resonant metasurfaces”, ACS Photonics 6, 1002–1009 (2019).
 A. Vaskin, S. Mashhadi, M. Steinert, K. Chong, D. Keene, S. Nanz, A. Abass , E. Rusak, D.-Y. Choi, I. Fernandez-Corbaton, T. Pertsch, C. Rockstuhl, M. Noginov, Y. Kivshar, D. Neshev, N. Noginova, and I. Staude, “Manipulation of magnetic dipole emission from Eu3+ with Mie-resonant dielectric metasurfaces”, Nano Lett. 19, 1015 (2019).
 F. Löchner, A. Fedotova, S. Liu, G. Keeler, G. Peake, S. Saravi, M. Shcherbakov, S. Burger, A. Fedyanin, I. Brener, T. Pertsch, F. Setzpfandt, I. Staude, “Polarization-Dependent Second Harmonic Diffraction from Resonant GaAs Metasurfaces”, ACS Photonics 5, 1786 (2018).
 A. Komar, Z. Fang, J. Bohn, J. Sautter, M. Decker, A. Miroshnichenko, T. Pertsch, I. Brener, Yu. S. Kivshar, I. Staude, and D. N. Neshev, „Electrically Tunable All-Dielectric Metasurfaces”, Appl. Phys. Lett. 110, 071109 (2017).
 C. Zou, A. Komar, S. Fasold, J. Bohn, A. A. Muravsky, A. A. Murauski, T. Pertsch, D. N. Neshev and I. Staude, “Electrically Tunable Transparent Displays for Visible Light Based on Dielectric Metasurfaces”, ACS Photonics 6, 1533 (2019).
1. A. Vaskin, S. Liu, A. Sadhvikas, P. P.Vabishchevich, M. Zilk, Y. Yang,G. Balarishnan, M. B. Sinclair, T. Pertsch, I. Brener, and I. Staude, “Manipulation of quantum dot emission with semiconductor metasurfaces exhibiting magnetic quadrupole resonances”, Opt. Express 29, 5567-5579 (2021).
Highlighted as an Editor's Pick.
2. F. J.F. Löchner, A. George, K. Koshelev, T. Bucher, E. Najafidehaghani, A. Fedotova, D. Y. Choi, T. Pertsch, I. Staude, Y. Kivshar, A. Turchanin, and F. Setzpfandt, „Hybridization of dielectric metasurfaces with chemical vapor deposition grown MoS2 monolayers for enhanced second-harmonic generation“, ACS Photonics 8, 218–227 (2021). https://doi.org/10.1021/acsphotonics.0c01375
3. A. Fedotova, M. Younesi, J. Sautter, A. Vaskin, F. J. F. Löchner, M. Steinert, R. Geiss, T. Pertsch, I. Staude, and F. Setzpfandt, “Second-harmonic generation in resonant nonlinear metasurfaces based on lithium niobate“, Nano Lett. 20, 8608-8614 (2020).
4. T. Santiago-Cruz, A. Fedotova, V. Sultanov, M. A. Weißflog, D. Arslan, M. Younesi, T. Pertsch, I. Staude, F. Setzpfandt, and M. V. Chekhova, “Spontaneous Parametric Down-Conversion from Resonant Metasurfaces”, arXiv preprint arXiv:2103.08524 (2021).
5. Y. D. Sırmacı, Z. Tang, S. Fasold, C. Neumann, T. Pertsch, A. Turchanin, and I. Staude, “Plasmonic Metasurfaces Situated on Ultrathin Carbon Nanomembranes”, ACS Photonics 7, 1060-1066 (2020).