Comment on "Far-field microscopy with a nanometer-scale resolution based on the in-plane image magnification by surface plasmon polaritons"

Spatial Focusing of Surface Polaritons Based on Cross-Phase Modulation

We theoretically study the spatial focusing of surface polaritons (SPs) in a negative index metamaterial (NIMM)-atomic gas interface waveguide system, based on cross phase modulation (XPM) in a tripod type double electromagnetically induced transparency (EIT) scheme. In the linear region, we realize the low loss stable propagation of SPs, and the group velocities of the probe and signal fields are well matched via double EIT. In the nonlinear region, we show that giant enhancement of the XPM can be obtained. Using a narrow optical soliton in free space, we realize spatial focusing of the SPs s…

Surface-Plasmon-Polariton Laser based on an Open-Cavity Fabry-Perot Resonator

Recent years have witnessed growing interest in the development of small-footprint lasers for potential applications in small-volume sensing and on-chip optical communications. Surface-plasmons, electromagnetic modes evanescently confined to metal-dielectric interfaces, offer an effective route to achieving lasing at nanometer-scale dimensions when resonantly amplified in contact with a gain-medium. Here, we achieve visible frequency ultra-narrow linewidth lasing at room-temperature by leveraging surface plasmons propagating in an open Fabry-Perot cavity formed by a flat metal surface coated w…

Hyperbolic phonon-polaritons in boron nitride for near-field optical imaging

Optical imaging beyond the diffraction limit was one of the primary motivations for negative-index metamaterials, resulting in Pendry's perfect lens and the more attainable superlens. While these approaches offer sub-diffractional resolution, they do not provide a mechanism for magnification of the image. Hyperbolic (or indefinite-permittivity) metamaterials have been theoretically considered and experimentally demonstrated to provide simultaneously subdiffractive imaging and magnification; however, they are plagued with low efficiency and complex fabrication. In this work, we present theoreti…

近场增强：通过CdO条纹中的等离激元-声子极化激元耦合实现

Near Field Enhancement via Plasmon Phonon Polariton Coupling with CdO Stripes

本研究通过干法刻蚀制备CdO条纹阵列，实现局域表面等离激元与声子极化激元的强耦合，实验和模拟证明共振时产生混合模式，近场增强超1000倍，为高性能红外传感平台提供新途径。

Spectrally enhancing near-field radiative transfer between gold gratings by exciting magnetic polariton in nanometric vacuum gaps

In the present work, we theoretically demonstrate that near field radiative transport between one dimensional periodic grating microstructures separated by nanometer vacuum gaps can be spectrally enhanced by exciting magnetic polariton. Fluctuational electrodynamics that incorporates scattering matrix theory with rigorous coupled wave analysis is employed to exactly calculate the near field radiative flux between two gold gratings. Besides the well known coupled surface plasmon polaritons, the radiative flux can be also spectrally enhanced due to magnetic polariton, which is excited in the gap…

Internal nanostructure diagnosis with hyperbolic phonon polaritons in hexagonal boron nitride

Imaging materials and inner structures with resolution below the diffraction limit has become of fundamental importance in recent years for a wide variety of applications. In this work, we report sub-diffractive internal structure diagnosis of hexagonal boron nitride by exciting and imaging hyperbolic phonon polaritons. Based on their unique propagation properties, we are able to accurately locate defects in the crystal interior with nanometer resolution. The precise location, size and geometry of the concealed defects is reconstructed by analyzing the polariton wavelength, reflection coeffici…

Near-field infrared nano-spectroscopy of surface phonon-polariton resonances

We present combined experimental and numerical work on light-matter interactions at nanometer length scales. We report novel numerical simulations of near-field infrared nanospectroscopy that consider, for the first time, detailed tip geometry and have no free parameters. Our results match published spectral shapes of amplitude and phase measurements even for strongly resonant surface phonon-polariton (SPhP) modes. They also verify published absolute scattering amplitudes for the first time. A novel, ultrabroadband light source enables near-field amplitude and phase acquisition into the far-in…

银纳米线中表面等离子体极化子的实时传播

Real-time surface plasmon polariton propagation in silver nanowires

本文通过电子能量损失光谱技术研究银纳米线中等离子体激发的实时动态，分析了电子与等离子体激发的相互作用，为等离子体传感器和量子光学应用提供理论支持。

Addressing the impact of surface roughness on epsilon-near-zero substrates

Epsilon-near-zero (ENZ) media have been very actively investigated due to their unconventional wave phenomena and strengthened nonlinear response. However, the technological impact of ENZ media will be determined by the quality of realistic ENZ materials, including material loss and surface roughness. Here, we provide a comprehensive experimental study of the impact of surface roughness on ENZ substrates. Using silicon carbide (SiC) substrates with artificially induced roughness, we analyze samples whose roughness ranges from a few to hundreds of nanometer size-scales. It is concluded that ENZ…

Generation and Detection of Surface Plasmon Polaritons by Transition Metal Dichalcogenides for Chip-level Electronic-Photonic Integrated Circuits

The monolithic integration of electronics and photonics has attracted enormous attention due to its potential applications. However, the realization of such hybrid circuits has remained a challenge because it requires optical communication at nanometer scales. A major challenge to this integration is the identification of a suitable material. After discussing the material aspect of the challenge, we identified atomically thin transition metal dichalcogenides (TMDs) as a perfect material platform to implement the circuit. The selection of TMDs is based on their very distinct property: monolayer…

Coupling emission from single localized defects in 2D semiconductor to surface plasmon polaritons

Coupling of an atom-like emitter to surface plasmons provides a path toward significant optical nonlinearity, which is essential in quantum information processing and quantum networks. A large coupling strength requires nanometer-scale positioning accuracy of the emitter near the surface of the plasmonic structure, which is challenging. We demonstrate the coupling of single localized defects in a tungsten diselenide (WSe2) monolayer self-aligned to the surface plasmon mode of a silver nanowire. The silver nanowire induces a strain gradient on the monolayer at the overlapping area, leading to t…

Plasmonic Spin-Hall Effect of propagating Surface Plasmon Polaritons in Ni$_{80}$Fe$_{20}$ microstructures

Photoexcitation and shaping of a propagating surface plasmon polariton (SPP) on silver and gold microstructures are well established and lead to the discovery of the plasmonic spin-Hall effect recently. Whereas silver is often the material of choice due to its exceptional low plasma frequency and weak damping, similar observations have not been reported for ferromagnetic metals. In this work, we report on propagating SPPs on Ni$_{80}$Fe$_{20}$ microstructures imaged by photoemission electron microscopy (PEEM) in combination with a tunable femtosecond laser system at MHz repetition rate. Circul…

Van der Waals enhancement of optical atom potentials via resonant coupling to surface polaritons

Contemporary experiments in cavity quantum electrodynamics (cavity QED) with gas-phase neutral atoms rely increasingly on laser cooling and optical, magneto-optical or magnetostatic trapping methods to provide atomic localization with sub-micron uncertainty. Difficult to achieve in free space, this goal is further frustrated by atom-surface interactions if the desired atomic placement approaches within several hundred nanometers of a solid surface, as can be the case in setups incorporating monolithic dielectric optical resonators such as microspheres, microtoroids, microdisks or photonic crys…

利用光子关联阴极荧光揭示纳米金刚石中氮-空位中心耦合至传播和局域表面等离激元的Purcell效应

Purcell effect of nitrogen-vacancy centers in nanodiamond coupled to propagating and localized surface plasmons revealed by photon-correlation cathodoluminescence

本研究结合扫描电子显微镜阴极荧光与干涉测量法，利用纳米金刚石氮-空位中心作为量子发射体，首次在纳米分辨率下实验揭示了其与表面等离极化激元耦合产生的Purcell效应及寿命缩短现象。

Numerical simulation studies of nano-scale Surface plasmon components: waveguides, splitters and filters

In this paper, we theoretically and numerically demonstrate a two-dimensional Metal-Dielectric-Metal (MDM) waveguide based on finite-difference time-domain simulation of the propagation characteristics of surface plasmon polaritons (SPPs). For practical applications, we propose a plasmonic Y-branch waveguide based on MDM structure for high integration. The simulation results show that the Y-branch waveguide proposed here makes optical splitter with large branching angle (~180 degree) come true. We also introduce a finite array of periodic tooth structure on one surface of the MDM waveguide whi…

Wide field fluorescence epi-microscopy behind a scattering medium enabled by speckle correlations

Fluorescence microscopy is widely used in biological imaging, however scattering from tissues strongly limits its applicability to a shallow depth. In this work we adapt a methodology inspired from stellar speckle interferometry, and exploit the optical memory effect to enable fluorescence microscopy through a turbid layer. We demonstrate efficient reconstruction of micrometer-size fluorescent objects behind a scattering medium in epi-microscopy, and study the specificities of this imaging modality (magnification, field of view, resolution) as compared to traditional microscopy. Using a modifi…

静电超晶格电势的等离子体偏振传感

Plasmonic polarization sensing of electrostatic superlattice potentials

本研究利用红外纳米成像与纳米光电流测量，探究石墨烯-扭曲六方氮化硼异质结的等离子体特性，发现石墨烯等离子体可用于偏振织构传感，且该t-BN为亚铁电体而非此前认为的铁电体。

用于面内偏振近场显微镜和光谱学的双针尖

Double tips for in-plane polarized near-field microscopy and spectroscopy

本文提出双针尖技术，提供面内偏振，增强近场成像与光谱性能，虽分辨率略低，但支持偏振控制，拓展纳米材料研究范围。

SPP-MIM杂化超薄膜：一种兼具SPR与LSPR优点的生物传感结构

SPP-MIM hybridization meta-film: a biosensing structure uniting the merits of SPR and LSPR

本文提出SPP-MIM杂化超薄膜生物传感结构，通过杂化SPP与MIM间隙等离激元，在保持平坦界面的同时显著缩短倏逝深度并提高表面灵敏度，为将LSPR设计转化为稳定生物传感器提供了新途径。

Light scattering from self-affine fractal silver surfaces with nanoscale cutoff: Far-field and near-field calculations

We study the light scattered from randomly rough, one-dimensional self-affine fractal silver surfaces with nanoscale lower cutoff, illuminated by s- or p-polarized Gaussian beams a few microns wide. By means of rigorous numerical calculations based on the Green theorem integral equation formulation, we obtain both the far- and near-field scattered intensities. The influence of diminishing the fractal lower scale cutoff (from below a hundred, down to a few nanometers) is analyzed in the case of both single realizations and ensemble average magnitudes. For s polarization, variations are small in…

Dynamical Tuning of Energy Transfer Efficiency on a Graphene Monolayer

We present in this contribution a theoretical investigation of the spontaneous emission and energy transfer rates between quantum systems placed above a monolayer of conducting graphene. The conditions for strong and weak coupling between a quantum system and the surface plasmon-polariton of graphene are determined and, subsequently, we focus exclusively on the weak coupling regime. We then calculate the dispersion relation of the surface plasmon mode on graphene and, by varying the chemical potential, show a good control of its resonance frequency. Using a Green's tensor formalism, we calcula…

Wafer-Bonded Surface Plasmon Waveguide Biosensors with In-Plane Microfluidic Interfaces

Biosensors exploiting long-range surface plasmon polariton (LRSPP) waveguides comprised of Au stripes embedded in Cytop with integrated and encapsulated microfluidic channels are fabricated and demonstrated. A fabrication approach was devised where the lower cladding and recessed Au stripes are fabricated on a Si substrate, and the upper cladding and microfluidic channels are fabricated on a glass substrate, followed by wafer bonding to assemble the wafers into complete structures. The bond is centered over the full length of the optical path, yet no evidence of optical scattering or excess lo…