Secondary Electron Cloaking with Broadband Plasmonic Resonant Absorbers.

Scanning electron microscopy (SEM) is one of the most powerful tools for nanoscale inspection and imaging. It is broadly used for biomedicine, materials science, and nanotechnology, enabling spatial resolution beyond the optical diffraction limit. In SEM, a high-energy electron beam illuminates a specimen, and the emitted secondary electrons are routed to a positively biased, synchronized detector for image creation. Here, for the first time, we experimentally demonstrate a cloaking of metallic objects from a secondary electron image. We make a metallic disc with a diameter of 300 nm almost invisible to a secondary electron detector with <5 nm spatial resolution. The secondary electron cloaking is based on broadband optical radiation absorption in the near field. Our secondary electron images are in good agreement with full-wave numerical solution of Maxwell's equations at optical frequencies, confirming the concept of secondary electron cloaking based on broadband optical radiation absorption.

[1]  P. Etchegoin,et al.  An analytic model for the optical properties of gold. , 2006, The Journal of chemical physics.

[2]  A. Kahn,et al.  How do electronic carriers cross Si-bound alkyl monolayers? , 2005, Physical review letters.

[3]  P. Renucci,et al.  Probing carrier dynamics in nanostructures by picosecond cathodoluminescence , 2005, Nature.

[4]  Huanyang Chen,et al.  Conformal transformation optics , 2014, Nature Photonics.

[5]  Z. Zalevsky,et al.  Wireless Communication with Nanoplasmonic Data Carriers: Macroscale Propagation of Nanophotonic Plasmon Polaritons Probed by Near-Field Nanoimaging. , 2017, Nano letters.

[6]  David R. Smith,et al.  A full-parameter unidirectional metamaterial cloak for microwaves. , 2013, Nature materials.

[7]  A. Polman,et al.  Plasmonic whispering gallery cavities as optical nanoantennas. , 2011, Nano letters.

[8]  A. Polman,et al.  Single-photon generation by electron beams. , 2011, Nano letters.

[9]  A. Gaeta,et al.  Demonstration of temporal cloaking , 2011, Nature.

[10]  M. Moskovits.  Hot Electrons Cross Boundaries , 2011, Science.

[11]  F. D. Abajo,et al.  Optical excitations in electron microscopy , 2009, 0903.1669.

[12]  David C. Joy,et al.  Fundamentals of Scanning Electron Microscopy (SEM) , 2006 .

[13]  David Cahen,et al.  Comparison of Electronic Transport Measurements on Organic Molecules , 2003 .

[14]  Zeev Zalevsky,et al.  Enabling High Efficiency Nanoplasmonics with Novel Nanoantenna Architectures , 2015, Scientific Reports.

[15]  Yu Luo,et al.  Macroscopic invisibility cloaking of visible light , 2010, Nature communications.

[16]  O. Stéphan,et al.  Electron Energy Loss Spectroscopy imaging of surface plasmons at the nanometer scale. , 2016, Ultramicroscopy.

[17]  J. Aizpurua,et al.  Plasmonic excitation and manipulation with an electron beam , 2012 .

[18]  P. Ginzburg,et al.  Plasmonic nanoantennas for broad-band enhancement of two-photon emission from semiconductors. , 2010, Nano letters.

[19]  Christian Girard,et al.  Electron energy losses and cathodoluminescence from complex plasmonic nanostructures: spectra, maps and radiation patterns from a generalized field propagator , 2014 .

[20]  N. Fang,et al.  Imaging of plasmonic modes of silver nanoparticles using high-resolution cathodoluminescence spectroscopy. , 2009, ACS nano.

[21]  Z. Zalevsky,et al.  Observing Optical Plasmons on a Single Nanometer Scale , 2014, Scientific Reports.

[22]  Z. Zalevsky,et al.  Secondary Electron Imaging of Light at the Nanoscale. , 2017, ACS nano.

[23]  M. Brongersma,et al.  Plasmonics: Harvest season for hot electrons. , 2013, Nature nanotechnology.

[24]  A. Polman,et al.  Optical properties of single plasmonic holes probed with local electron beam excitation. , 2014, ACS nano.

[25]  Zeev Zalevsky,et al.  Towards integrated nanoplasmonic logic circuitry. , 2013, Nanoscale.