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Nature Materials. doi:10.1038/nmat4609

Authors: Kandammathe Valiyaveedu Sreekanth, Yunus Alapan, Mohamed ElKabbash, Efe Ilker, Michael Hinczewski, Umut A. Gurkan, Antonio De Luca & Giuseppe Strangi

Nature Photonics 10, 209 (2016). doi:10.1038/nphoton.2016.55

Author: Oliver Graydon

Nature Photonics 10, 210 (2016). doi:10.1038/nphoton.2016.40

Authors: Martin Wagner & Mengkun Liu

Near- and mid-infrared plasmonics are exciting research areas with applications in nanoscale energy concentration, sensing or ultrafast switching for telecommunication. Now, a new efficient way to manipulate plasmon resonances in semiconductor nanoarrays at ultrafast timescales has been found.

Nature Photonics 10, 208 (2016). doi:10.1038/nphoton.2016.42

Author: Guillaume Schull

An optoelectronic prototype based on a self-assembled molecular junction to controllably excite propagating surface plasmons has been developed.

A cosmological simulation containing only dark matter is relatively easy to run, but adding gas, stars, and galaxies to the model requires sophisticated hydrodynamics and subgrid physics. – [Read More]

Article

Reconstruction of super resolution structured illumination microscopy (SR-SIM) datasets typically relies upon commercial software. Here Müller et al. present an open-source ImageJ plugin to facilitate reconstruction of SR-SIM data from a broad range of microscopy platforms.

Nature Communications doi: 10.1038/ncomms10980

Authors: Marcel Müller, Viola Mönkemöller, Simon Hennig, Wolfgang Hübner, Thomas Huser

Gabriel D. Bernasconi, Jérémy Butet, Olivier J. F. Martin
Using a surface integral equation approach based on the tangential Poggio–Miller–Chang–Harrington–Wu–Tsai formulation, we present a full wave analysis of the resonant modes of 3D plasmonic nanostructures. This method, combined with the evaluation of ... [J. Opt. Soc. Am. B 33, 768-779 (2016)]

Deterministically integrating semiconductor quantum emitters with plasmonic nano-devices paves the way towards chip-scale integrable, true nanoscale quantum photonics technologies. For this purpose, stable and bright semiconductor emitters are needed, which moreover allow for CMOS-compatibility and optical activity in the telecommunication band. Here, we demonstrate strongly enhanced light-matter coupling of single near-surface ($<10\,nm$) InAs quantum dots monolithically integrated into electromagnetic hot-spots of sub-wavelength sized metal nanoantennas. The antenna strongly enhances the emission intensity of single quantum dots by up to $\sim16\times$, an effect accompanied by an up to $3.4\times$ Purcell-enhanced spontaneous emission rate. Moreover, the emission is strongly polarised along the antenna axis with degrees of linear polarisation up to $\sim85\,\%$. The results unambiguously demonstrate the efficient coupling of individual quantum dots to state-of-the-art nanoantennas. Our work provides new perspectives for the realisation of quantum plasmonic sensors, step-changing photovoltaic devices, bright and ultrafast quantum light sources and efficent nano-lasers.

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Nature Materials 15, 377 (2016). doi:10.1038/nmat4605

Authors: Daeyeon Lee & Sang Eon Han

Macroscopic deformation can induce chirality in initially achiral nanoparticle composites, and reversibly modulate their chiroptical properties.

We discuss nanophotonic structures composed of high-index dielectric nanoparticles and present several basic approaches for numerical study of their collective optical response. We also provide comparison on the collective optical properties of dielectric and plasmonic structures, and review experimental demonstrations of Fano resonances in all-dielectric nanoparticle oligomers.

Impulsive interband excitation with femtosecond near-infrared pulses establishes a plasma response in intrinsic germanium structures fabricated on a silicon substrate. This direct approach activates the plasmonic resonance of the Ge structures and enables their use as optical antennas up to the mid-infrared spectral range. The optical switching lasts for hundreds of picoseconds until charge recombination red-shifts the plasma frequency. The full behavior of the structures is modeled by the electrodynamic response established by an electron-hole plasma in a regular array of antennas.

Xianghong Kong, Gaobiao Xiao
In this paper, an approximate model is presented to understand Fano resonance observed in the Mie scattering from a homogeneous dielectric sphere. By using the model, we can analyze the Fano parameters and resonance widths of the dielectric spheres with given lossless high-permittivity materials. ... [J. Opt. Soc. Am. A 33, 707-711 (2016)]

We introduce a definition of the electromagnetic chirality of an object and show that it has an upper bound. Reciprocal objects attain the upper bound if and only if they are transparent for all the fields of one polarization handedness (helicity). Additionally, electromagnetic duality symmetry, i.e., helicity preservation upon interaction, turns out to be a necessary condition for reciprocal objects to attain the upper bound. We use these results to provide requirements for the design of such extremal objects. The requirements can be formulated as constraints on the polarizability tensors for dipolar objects or on the material constitutive relations for continuous media. We also outline two applications for objects of maximum electromagnetic chirality: a twofold resonantly enhanced and background-free circular dichroism measurement setup, and angle-independent helicity filtering glasses. Finally, we use the theoretically obtained requirements to guide the design of a specific structure, which we then analyze numerically and discuss its performance with respect to maximal electromagnetic chirality.

Metasurfaces are planar optical elements that hold promise for overcoming the limitations of refractive and conventional diffractive optics1-3. Dielectric metasurfaces demonstrated thus far4-10 are limited to transparency windows at infrared wavelengths because of significant optical absorption and loss at visible wavelengths. It is critical that new materials and fabrication techniques be developed for dielectric metasurfaces at visible wavelengths to enable applications such as three-dimensional displays, wearable optics and planar optical systems11. Here, we demonstrate high performance titanium dioxide dielectric metasurfaces in the form of holograms for red, green and blue wavelengths with record absolute efficiency (>78%). We use atomic layer deposition of amorphous titanium dioxide that exhibits low surface roughness of 0.738 nm and ideal optical properties. To fabricate the metasurfaces we use a lift-off-like process that allows us to produce highly anisotropic nanofins with shape birefringence. This process is applicable to any optical element and can be implemented using a broad class of materials.

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Nanolights are bright, beautiful — and increasingly useful

Nature 531, 7592 (2016). http://www.nature.com/doifinder/10.1038/531026a

Author: XiaoZhi Lim

Virus-sized particles that fluoresce in every colour could revolutionize applications from television displays to cancer treatment.

While metamaterials are often desirable for near-field functions, such as perfect lensing, or cloaking, they are often quantified by their response to plane waves from the far field. Here, we present a theoretical analysis of the local density of states near lattices of discrete magnetic scatterers, i.e., the response to near field excitation by a point source. Based on a point-dipole theory using Ewald summation and an array scanning method, we can swiftly and semi-analytically evaluate the local density of states (LDOS) for magnetoelectric point sources in front of an infinite two-dimensional (2D) lattice composed of arbitrary magnetoelectric dipole scatterers. The method takes into account radiation damping as well as all retarded electrodynamic interactions in a self-consistent manner. We show that a lattice of magnetic scatterers evidences characteristic Drexhage oscillations. However, the oscillations are phase shifted relative to the electrically scattering lattice consistent with the difference expected for reflection off homogeneous magnetic respectively electric mirrors. Furthermore, we identify in which source-surface separation regimes the metasurface may be treated as a homogeneous interface, and in which homogenization fails. A strong frequency and in-plane position dependence of the LDOS close to the lattice reveals coupling to guided modes supported by the lattice.

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Nature Photonics 10, 153 (2016). doi:10.1038/nphoton.2016.25

Author: Noriaki Horiuchi

We obtain the local density of states (LDOS) for any nanoplasmonic system in the frequency range dominated by a localized surface plasmon. By including the Ohmic losses in a consistent way, we show that the plasmon LDOS is proportional to the local field intensity normalized by the absorbed power. We obtain explicit formulas for the energy transfer (ET) between quantum emitters and plasmons as well as between donors and acceptors situated near a plasmonic structure. In the latter case, we find that the plasmon-assisted ET rate is proportional to the LDOS product at the donor and acceptor positions, obtain, in a general form, the plasmon ET enhancement factor, and establish the transition onset between Forster-dominated and plasmon-dominated ET regimes.

We examine the efficacy of Dark-mode plasmonics as a platform for enhanced magneto-optics. Dark-mode of a small particle consists of two co-existing equal-intensity and mutually opposing dipolar excitations. Each of these two opposing dipoles may even resonate at or near the dark-mode frequency, but the net dipole moment vanishes due to the mutual cancelation between the opposing dipoles. We show that application of external magnetic bias may alleviate the intense destructive interference. Furthermore, under external magnetic bias the opposing dark-resonances of a plasmonic particle shift in opposite directions and create a region of extremely sensitive Faraday rotation. We show that the magnetized dark resonance in lossless Ag-like particle may provide more than 20 degrees rotation under magnetic fields of the order of 1-2 Tesla, exhibiting magneto-plasmonic activity that is 2-3 orders of magnitude larger than that observed in conventional plasmonic particle of the same material.