All-optical dynamic focusing of light via coherent absorption in a plasmonic metasurface

Vision, microscopy, imaging, optical data projection and storage all depend on focusing of light. Dynamic focusing is conventionally achieved with mechanically reconfigurable lenses, spatial light modulators or microfluidics. Here we demonstrate that dynamic control of focusing can be achieved through coherent interaction of optical waves on a thin beam splitter. We use a nanostructured plasmonic metasurface of subwavelength thickness as the beam splitter, allowing operation in the regimes of coherent absorption and coherent transparency. Focusing of light resulting from illumination of the plasmonic metasurface with a Fresnel zone pattern is controlled by another patterned beam projected on the same metasurface. By altering the control pattern, its phase, or its intensity, we switch the lens function on and off, and alter the focal spot’s depth, diameter and intensity. Switching occurs as fast as the control beam is modulated and therefore tens of gigahertz modulation bandwidth is possible with electro-optical modulators, which is orders of magnitude faster than conventional dynamic focusing technologies.

[1]  R. Osgood,et al.  Integrated optical modulators and switches using coherent perfect loss. , 2013, Optics letters.

[2]  B. Hendriks,et al.  Electrowetting-Based Variable-Focus Lens for Miniature Systems , 2005 .

[3]  Nikolay I. Zheludev,et al.  Ultrafast all-optical switching via coherent modulation of metamaterial absorption , 2014 .

[4]  Nikolay I. Zheludev,et al.  Coherent control of optical polarization effects in metamaterials , 2015, Scientific Reports.

[5]  S. Bernet,et al.  What spatial light modulators can do for optical microscopy , 2011 .

[6]  Nikolay I. Zheludev,et al.  Controlling light with light using coherent metadevices: all-optical transistor, summator and invertor , 2014, Light: Science & Applications.

[7]  Brendon O. Watson,et al.  SLM Microscopy: Scanless Two-Photon Imaging and Photostimulation with Spatial Light Modulators , 2008, Frontiers in neural circuits.

[8]  Nikolay I. Zheludev,et al.  Planar super-oscillatory lens for sub-diffraction optical needles at violet wavelengths , 2014, Scientific Reports.

[9]  N. Zheludev,et al.  11-fs dark pulses generated via coherent absorption in plasmonic metamaterial. , 2017, Optics express.

[10]  Okan K. Ersoy,et al.  Diffraction, Fourier Optics and Imaging , 2006 .

[11]  Sidney F. Ray,et al.  Applied Photographic Optics: Lenses and Optical Systems for Photography, Film, Video and Electronic Imaging , 1994 .

[12]  Luke P. Lee,et al.  Tunable liquid-filled microlens array integrated with microfluidic network. , 2003, Optics express.

[13]  Sidney F. Ray,et al.  Applied Photographic Optics: Lenses and optical systems for photography, film, video, electronic and digital imaging , 2002 .

[14]  Yidong Chong,et al.  Time-Reversed Lasing and Interferometric Control of Absorption , 2011, Science.

[15]  D. Faccio,et al.  Coherent control of light interaction with graphene. , 2014, Optics letters.

[16]  Miceli,et al.  Diffraction-free beams. , 1987, Physical review letters.

[17]  Hui Cao,et al.  Coherent perfect absorbers: Time-reversed lasers , 2010, CLEO/QELS: 2010 Laser Science to Photonic Applications.

[18]  P. L. Kelley,et al.  Self-focusing of optical beams , 1965, International Quantum Electronics Conference, 2005..

[19]  W. T. Chen,et al.  A combinatorial approach to metamaterials discovery , 2010, 1009.0391.

[20]  João Valente,et al.  Two-dimensional control of light with light on metasurfaces , 2016, Light: Science & Applications.

[21]  K. Dholakia,et al.  Tunable Bessel light modes: engineering the axial propagation. , 2009, Optics express.

[22]  A. Bruce Langdon,et al.  Self-Modulation and Self-Focusing of Electromagnetic Waves in Plasmas , 1974 .

[23]  David R. Smith,et al.  Terahertz compressive imaging with metamaterial spatial light modulators , 2014, Nature Photonics.

[24]  J. Jeffers,et al.  Coherent perfect absorption in deeply subwavelength films in the single-photon regime , 2015, Nature Communications.

[25]  Sukosin Thongrattanasiri,et al.  Complete optical absorption in periodically patterned graphene. , 2012, Physical review letters.

[26]  Yi-Hsin Lin,et al.  A Review of Electrically Tunable Focusing Liquid Crystal Lenses , 2011 .

[27]  Nikolay I. Zheludev,et al.  Super-oscillatory optical needle , 2013 .

[28]  P. Lallemand,et al.  Self-Focusing of Laser Beams and Stimulated Raman Gain in Liquids , 1965 .

[29]  J. Goodman.  Introduction to Fourier optics , 1969 .

[30]  Weisong Wang,et al.  Variable-focusing microlens with microfluidic chip , 2004 .

[31]  Nikolay I. Zheludev,et al.  All-Optical Pattern Recognition and Image Processing on a Metamaterial Beam Splitter , 2017 .

[32]  Nikolay I. Zheludev,et al.  All-optical multichannel logic based on coherent perfect absorption in a plasmonic metamaterial , 2016 .

[33]  Mark R. Dennis,et al.  A super-oscillatory lens optical microscope for subwavelength imaging. , 2012, Nature materials.

[34]  Sindy K. Y. Tang,et al.  Dynamically reconfigurable liquid-core liquid-cladding lens in a microfluidic channel. , 2008, Lab on a chip.

[35]  R. Agarwal,et al.  Tunable Metasurface and Flat Optical Zoom Lens on a Stretchable Substrate. , 2016, Nano letters.

[36]  N. Zheludev,et al.  Coherent control of optical activity and optical anisotropy of thin metamaterials , 2013, 1312.0414.

[37]  Nikolay I. Zheludev,et al.  Controlling light-with-light without nonlinearity , 2012, Light: Science & Applications.

[38]  Junjie Li,et al.  Tunable mid-infrared coherent perfect absorption in a graphene meta-surface , 2015, Scientific Reports.

[39]  Eric Plum,et al.  Coherent control of Snell's law at metasurfaces. , 2014, Optics express.