We propose a model accounting for plasmons within a two temperature description, to investigate the role of surface plasmon polaritons (SPP) in the energy redistribution between laser excited electrons and the lattice, leading to surface restructuring of the material. This energy transfer can lead to the creation of laser induced surface structures in metals illuminated by an ultrashort laser pulse. The Two Temperature Model + Plasmon (TTM+P) equations are constructed by applying perturbation theory on the energy-, momentum- and density conservation equations of free electrons in metals. We consider three subsystems: the lattice, the thermalized electrons and the SPP, subject to an external laser field irradiation. The interference between the laser and SPP fields leads to spatially modulated energy absorption by the electronic system, and, through electron-phonon collisions, periodically shapes the lattice temperature. A numerical analysis is performed on a 1D model for gold. We show the emergence of a periodic modulation of the lattice temperature, which may contribute to laser induced periodic surface structures (LIPSS).
We present new relations for calculation of phonon polaritons, plasmons and plasmon polaritons frequencies, which differ from the standard relations. So, we study the frequency of phonon polaritons in a two dimensional lattice with applications to CuO2 lattice. Next, we evaluate plasmon frequencies in graphene and in Cu2D and Cu3D metals. Further, we evaluate the frequency of surface plasmon polaritons at the Cu2D/air and Cu3D/air interfaces. The obtained results are in a good agreement with experimental data. Also, we present a correspondence between the potential vector and the displacement …
We study the spectra and damping of surface plasmon-polaritons in double graphene layer structures. It is shown that application of bias voltage between layers shifts the edge of plasmon absorption associated with the interband transitions. This effect could be used in efficient plasmonic modulators. We reveal the influence of spatial dispersion of conductivity on plasmonic spectra and show that it results in the shift of cutoff frequency to the higher values.
Coherent sub-THz phonons incident on a gold grating that is deposited on a dielectric substrate undergo diffraction and thereby induce an alteration of the surface plasmon-polariton resonance. This results in efficient high-frequency modulation (up to 110 GHz) of the structure's reflectivity for visible light in the vicinity of the plasmon-polariton resonance. High modulation efficiency is achieved by designing a periodic nanostructure which provides both plasmon-polariton and phonon resonances. Our theoretical analysis shows that the dynamical alteration of the plasmon-polariton resonance is …
Emission of photon pairs by an interface of asymmetric dielectric and thin metal film excited by a normally falling plane wave is considered. The excitation causes oscillations in time of the phase velocity of surface plasmon polaritons in the interface. This leads to the dynamical Casimir effect - the generation of pairs of surface plasmon polariton quanta, which transfer to photons outside the interface. In case of a properly chosen interface, the yield of two-photon emission may exceed that of usual spontaneous parametric down conversion.
Based on the semiclassical model Hamiltonian of the surface plasmon polariton and the nonequilibrium Green-function approach, we present a microscopic kinetic theory to study the influence of the electron scattering on the dynamics of the surface plasmon polariton in semiconductor nanowires. The damping of the surface plasmon polariton originates from the resonant absorption by the electrons (Landau damping), and the corresponding damping exhibits size-dependent oscillations and distinct temperature dependence without any scattering. The scattering influences the damping by introducing a broad…
We study the TE polarized electromagnetic surface wave propagating along the interface between materials with positive and negative magnetic permeability. Contrary to the TM polarized surface wave, the TE surface wave exhibits almost no radiation losses when scattered at semi-infinite dielectric interfaces.
The combination of plasmonic nanoparticles and graphene enhances the responsivity and spectral selectivity of graphene-based photodetectors. However, the small area of the metal-graphene junction, where the induced electron-hole pairs separate, limits the photoactive region to sub-micron length scales. Here, we couple graphene with a plasmonic grating and exploit the resulting surface plasmon polaritons to deliver the collected photons to the junction region of a metal-graphene-metal photodetector. This results into a 400% enhancement of responsivity and a 1000% increase in photoactive length,…
We study surface plasmon polaritons on topological insulator-vacuum interface. When the time-reversal symmetry is broken due to ferromagnetic coupling, the surface states exhibit magneto-optical Kerr effect. This effect gives rise to a novel transverse type surface plasmon polariton, besides the longitudinal type. In specific, these two types contain three different channels, corresponding to the pole of determinant of Fresnel reflection matrix. All three channels of surface plasmon polaritons display tight confinement, long lifetime and show strong light-matter coupling with a dipole emitter.
Graphene plasmonics is of great interest for compact optical devices working in broad frequency domains with ultrahigh speed and very low energy consumption. However, graphene plasmons damp out quickly on most substrates mainly due to scattering loss from substrate surface phonons and impurities. Here we discover a new hybridized plasmon-phonon polariton mode in graphene/h-BN van der Waals heterostructures, which enables ultralong hybrid plasmon lifetime up to 1.6 picosecond, the longest plasmon lifetime ever demonstrated. Such remarkably long lifetime arises from the coupling of long-lifetime…
We investigated, both experimentally and theoretically, the reflection phase shift (RPS) of one-dimensional plasmon polaritons. We launched 1D plasmon polaritons in carbon nanotube and probed the plasmon interference pattern using scanning near-field optical microscopy (SNOM) technique, through which a non-zero phase shift was observed. We further developed a theory to understand the nonzero phase shift of 1D polaritons, and found that the RPS can be understood by considering the evanescent field beyond the nanotube end. Interesting, our theory shows a strong dependence of RPS on polaritons wa…
We study a surface plasmon polariton mode that is strongly confined in the transverse direction and propagates along a periodically nanostructured metal-dielectric interface. We show that the wavelength of this mode is determined by the period of the structure, and may therefore, be orders of magnitude smaller than the wavelength of a plasmon-polariton propagating along a flat surface. This plasmon polariton exists in the frequency region in which the sum of the real parts of the permittivities of the metal and dielectric is positive, a frequency region in which surface plasmon polaritons do n…
We have investigated the spectrum of two-dimensional (2D) plasmon polaritons over the full range of magnetic fields. In our study, we investigate a disk-shaped two-dimensional electron system (2DES) with a metallic gate on the backside of the substrate. Importantly, we show that 2D plasmon polaritons hybridize with the TM$_0$ photonic mode of a dielectric waveguide formed by a sample substrate. We have developed a theory for plasmon-polaritons in an infinite 2DES. We find the experimental data to be in good agreement with the developed theory.
Optical field interacting with a topologically protected one-dimensional helical state is shown to support a one-dimensional plasmon-polariton that is characterized by a non-linear dispersion. In a two-dimensional Dirac magnet these electro-optical excitations are confined to domain walls, thus, offering a possibility to manipulate quantum optical states by altering magnetic domain configurations. An exact spectral equation for such a topological plasmon-polariton is derived.
It is well known that collective electronic excitations in fullerene C$_{60}$ are manifested as Mie plasmons, and in graphene (the limiting case of an infinitely large fullerene) collective excitations are of plasmon-polariton type. How the properties of plasmons change in fullerenes with intermediate sizes is poorly understood. This problem is considered in current paper in the framework of the GW approximation on the example of fullerenes C$_{60}$, C$_{240}$ and C$_{540}$. The calculations show that a high-frequency plasmon-polariton resonance begins to form in C$_{240}$, and in C$_{540}$ th…
With the unique possibilities for controlling light in nanoscale devices, graphene plasmonics has opened new perspectives to the nanophotonics community with potential applications in metamaterials, modulators, photodetectors, and sensors. This paper briefly reviews the recent exciting progress in graphene plasmonics. We begin with a general description for optical properties of graphene, particularly focusing on the dispersion of graphene-plasmon polaritons. The dispersion relation of graphene-plasmon polaritons of spatially extended graphene is expressed in terms of the local response limit …
Weyl semimetals have recently attracted extensive attention due to their anomalous band structure manifested by topological properties that lead to some unusual and unique physical properties. We investigate novel features of surface plasmon polaritons in a slot waveguide comprised from two semi-infinite Weyl semimetals. We consider symmetric Voigt-Voigt and Faraday-Faraday configurations for plasmon polaritons in two interfaces of waveguide and show that the resulting dispersion is symmetric and the propagation of surface plasmon polaritons is bidirectional. We introduce exotic and novel asym…
In a proposed book chapter surface plasmon polariton assisted optical switching in noble metal nanoparticle systems is discussed in the sub-band gap formalism.
We consider a hybrid structure formed by graphene and an insulating antiferromagnet, separated by a dielectric of thickness up to $d\simeq 500 \,nm$. When uncoupled, both graphene and the antiferromagnetic surface host their own polariton modes coupling the electromagnetic field with plasmons in the case of graphene, and with magnons in the case of the antiferromagnet. We show that the hybrid structure can host two new types of hybrid polariton modes. First, a surface magnon-plasmon polariton whose dispersion is radically changed by the carrier density of the graphene layer, including a change…
We study topological surface-plasmon-polaritons at optical frequencies in diffraction gratings formed by bipartite corrugated metal-dielectric gratings. To do so we implement the theory as developed in Della Valle and Longhi to describe the amplitude of the field by an emergent Schrödinger-like equation. The tri-harmonic grating generates a bipartite Kronig-Penney model. Topologically protected localised modes are then predicted to occur at the edges of the grating and at defects formed by the combination of two mirror antisymmetric corrugations, whose bulk invariant is a step-wise varying Zak…
It is shown that one can explore the optical conductivity of graphene, together with the ability of controlling its electronic density by an applied gate voltage, in order to achieve resonant coupling between an external electromagnetic radiation and surface plasmon-polaritons in the graphene layer. This opens the possibility of electrical control of the intensity of light reflected inside a prism placed on top of the graphene layer, by switching between the regimes of total reflection and total absorption. The predicted effect can be used to build graphene-based opto-electronic switches.
We theoretically investigate surface plasmon polaritons propagating in the thin-film Weyl semimetals. We show how the properties of surface plasmon polaritons are affected by hybridization between plasmons localized at the two metal-dielectric interfaces. Generally, this hybridization results in new mixed plasmon modes, which are called short-range surface plasmons and long-range surface plasmons, respectively. We calculate dispersion curves of these mixed modes for three principle configurations of the axion vector describing axial anomaly in Weyl semimetals. We show that the partial lack of …
Surface plasmon polariton (SPP) is an electromagnetic wave which is tightly localised beyond the diffraction limit at metallic surfaces. Recently, it is theoretically proposed that the angular momentum conversion between the SPP and electrons. In this work, we have successfully measured SPP induced spin currents, which proves the fact that the angular momenta are interconverted. Such conversion from light to a spin current can be used as a coupler in a next generation spintronic computing with optical data transfer or storage.
Polaritons are quasiparticles arising from the strong coupling of electromagnetic waves in cavities and dipolar oscillations in a material medium. In this framework, localized surface plasmon in metallic nanoparticles defining optical nanocavities have attracted increasing interests in the last decade. This interest results from their sub-diffraction mode volume, which offers access to extremely high photonic densities by exploiting strong scattering cross-sections. However, high absorption losses in metals have hindered the observation of collective coherent phenomena, such as condensation. I…
Surface plasmon polaritons in planar graphene superlattices with one-dimensional periodic mo-dulation of the band gap were studied. The interminiband contribution to the optical conductivity of this system was found by the equation of motion method for two cases: the Fermi level falls within one of the minigaps and the Fermi level is located within one of the minibands. It was shown that the optical conductivity of the system varies significantly in these cases. The spectra of surface plasmon polaritons in the system differs for them.
Excitation of multiple surface plasmon-polaritons(SPPs) by an equichiral sculptured thin film with a metal layer defect was studied theoretically in the Sarid configuration, using the transfer matrix method. Multiple SPP modes were distinguished from waveguide modes in optical absorption for p- polarized plane wave. The degree of localization of multiple SPP waves was investigated by calculation of the time averaged Poynting vector. The results showed that the long-range and short-range SPP waves can simultaneously be excited at both interfaces of metal core in this proposed structure which ma…
We introduce the quantum mechanical formalism for treating surface plasmon polariton scattering at an interface. Our developed theory - which is fundamentally different from the analogous photonic scenario - is used to investigate the possibility of plasmonic beamsplitters at the quantum level. Remarkably, we find that a wide-range of splitting ratios can be reached. As an application, we characterize a 50:50 plasmonic beamsplitter and investigate first-order quantum interference of surface plasmon polaritons. The results of this theoretical study show that surface plasmon beamsplitters are ab…
The resonant scattering of surface plasmon-polariton waves by embedded semiconductor quantum dots above the dielectric/metal interface is explored in the strong-coupling regime. In contrast to non-resonant scattering by a localized dielectric surface defect, a strong resonant peak in the scattering field spectrum is predicted and accompanied by two side valleys. The peak height depends nonlinearly on the amplitude of surface plasmon-polariton waves, reflecting the feedback dynamics from a photon-dressed electron-hole plasma inside the quantum dots. This unique behavior in the scattering field …
We study the coherent properties of plasmon polaritons optically excited on periodic nanostructures. The gold grains are coupled to a single mode photonic waveguide which exhibits a dramatically reduced transmission originating from the derived quantum interference. With a nonequilibrium description of Floquet-dressed polaritons we demonstrate the switching of light transmission through the waveguide due to sheer existence of intraband transitions in gold from right above the Fermi level driven by the external laser light.
Phonon polaritons in natural anisotropic crystals hold great promise for infrared nano-optics. However, the direct electrical control of these polaritons is difficult, preventing the development of active polaritonic devices. Here we propose the heterostructures of graphene on a biaxial crystal (α-phase molybdenum trioxide) slab and theoretically study the hybridized plasmon-phonon polaritons with dependence on the Fermi level of graphene from three aspects: dispersion relationships, iso-frequency contours, and the quantum spin Hall effects. We demonstrate the distinct wavelength tunability of…
We consider a simple cubic array of metallic nanoparticles supporting extended collective plasmons that arise from the near-field dipolar interaction between localized surface plasmons in each nanoparticle. We develop a fully analytical quantum theory of the strong-coupling regime between these collective plasmons and photons resulting in plasmon polaritons in the nanoparticle array. Remarkably, we show that the polaritonic band gap and the dielectric function of the metamaterial can be significantly modulated by the polarization of light. We unveil how such an anisotropic behavior in the plas…
Surface plasmon polaritons in a strained slab of a Weyl semimetal with broken time-reversal symmetry are investigated. It is found that the strain-induced axial gauge field reduces frequencies of these collective modes for intermediate values of the wave vector. Depending on the relative orientation of the separation of Weyl nodes in momentum space, the surface normal, and the direction of propagation, the dispersion relation of surface plasmon polaritons could be nonreciprocal even in a thin slab. In addition, strain-induced axial gauge fields can significantly affect the localization propert…
We study the collective, superradiant behavior in the system of emitter-dressed Ag nanorods. Starting from the Drude model for the plasmon oscillations, we arrive at a semi-empirical Hamiltonian describing the coupling between quantized surface plasmon modes and the quantum emitters that can be controlled by manipulating their geometry, spacing, and orientation. Further, identifying the lowest polariton mode as SP-states dressed by excitons in the vicinity of $k=0$, we examine conditions allowing for the polariton quantum phase transition. While the system is formally a 1D array, we show that …
Plasmonic structures are known to support the modes with subwavelength volumes in which the field matter interactions are greatly enhanced. Coupling between the molecular excitations and plasmons leading to formation of plexcitons has been investigated for a number of organic molecules. However, plasmon-exciton coupling in metal semiconductor structures have not experienced the same degree of attention. In this work we show that the very strong coupling regime in which the Rabi energy exceeds the exciton binding energy is attainable in semiconductor cladded plasmonic nanoparticles and leads to…
We theoretically investigate plasmon polaritons in cubic lattices of spherical metallic nanoparticles. The nanoparticles, each supporting triply-degenerate localized surface plasmons, couple through the Coulomb dipole-dipole interaction, giving rise to collective plasmons that extend over the whole metamaterial. The latter hybridize with photons forming plasmon polaritons, which are the hybrid light-matter eigenmodes of the system. We derive general analytical expressions to evaluate both plasmon and plasmon-polariton dispersions, and the corresponding eigenstates. These are obtained within a …
We propose a plasmonic device consisting of a concentric ring grating acting as an efficient tool for directional launching and detection of surface plasmon-polaritons (SPPs). Numerical simulations and optical characterizations are used to study the fabricated structured gold surface. We demonstrate that this circularly symmetrical plasmonic device provides an efficient interface between free space radiation and SPPs. This structure offers an excellent platform for the study of hybrid plasmonics in general and of plasmon-emitter couplings in particular, such as those occurring when exciting dy…
Herein, we report sub-wavelength propagation and directional out-coupling of whispering gallery modes (WGMs) of a fluorescent silica microsphere resonator mediated via plasmon polaritons in a single crystalline silver nanowire. Fluorescent spectral signatures of emission from the nanowire ends confirm efficient guiding of WGMs via nanowire plasmons. By employing Fourier plane optical microscopy, we reveal and quantify the directional fluorescence emission of WGMs from the ends of the nanowire. Given that the discussed geometry is self-assembled from a solution-phase, our results will find rele…
The effect of electromagnetic retardation on the spectrum of edge plasmons in a semi-infinite two-dimensional electron system is considered. The problem is reduced to complicated integral equations for the potentials, which are solved upon a major simplification of the kernel. The spatial distribution of the potentials, charges, and currents is analyzed. It is shown that edge plasmon polaritons in the high-conductivity two dimensional system are characterized by a high Q factor at all frequencies, including those lower than the inverse electron relaxation time.
We report a nano-infrared (IR) imaging study of trilayer graphene (TLG) with both ABA (Bernal) and ABC (rhombohedral) stacking orders using the scattering-type scanning near-field optical microscope (s-SNOM). With s-SNOM operating in the mid-IR region, we mapped in real space the surface plasmon polaritons (SPPs) of ABA-TLG and ABC-TLG, which are tunable with electrical gating. Through quantitative modeling of the plasmonic imaging data, we found that the plasmon wavelength of ABA-TLG is significantly larger than that of ABC-TLG, resulting in a sizable impedance mismatch and hence a strong pla…
Surface plasmon polaritons in graphene couple strongly to surface phonons in polar substrates leading to hybridized surface plasmon-phonon polaritons (SPPPs). We demonstrate that a surface acoustic wave (SAW) can be used to launch propagating SPPPs in graphene/h-BN heterostructures on a piezoelectric substrate like AlN, where the SAW-induced surface modulation acts as a dynamic diffraction grating. The efficiency of the light coupling is greatly enhanced by the introduction of the h-BN film as compared to the bare graphene/AlN system. The h-BN interlayer not only significantly changes the disp…
Transverse-electric (TE) surface plasmon polaritons are unique eigenmodes of a homogeneous graphene layer that are tunable with the chemical potential and temperature. However, as their dispersion curve spectrally lies just below the light line, they cannot be resonantly excited by an externally incident wave. Here, we propose a way of exciting the TE modes and tuning their peaks in the transmission by introducing a one-dimensional graphene grating. Using the scattering-matrix formalism, we show that periodic modulations of graphene make the transmission more pronounced, potentially allowing f…
The dispersion relation of surface plasmon polaritons in graphene that includes optical losses is often obtained for complex wave vectors while the frequencies are assumed to be real. This approach, however, is not suitable for describing the temporal dynamics of optical excitations and the spectral properties of graphene. Here, we propose an alternative approach that calculates the dispersion relation in the complex frequency and real wave vector space. This approach provides a clearer insight into the optical properties of a graphene layer and allows us to find the surface plasmon modes of a…
The current (voltage) responsivity of the superlattice-based diode detectors in the terahertz frequency band which includes the region of the polar optical phonon frequencies has been analyzed theoretically. Within the framework of the equivalent circuit approach an electro-dynamical model which allows one to analyze the responsivity taking into account the plasmon polariton excitation both in the substrate and in the contact layers of the diodes has been suggested. It has been shown that the presence of the plasmon polariton excitation gives rise to strong features in the frequency dependence…
The realization and control of polaritons is of paramount importance in the prospect of novel photonic devices. Here, we investigate the emergence of plasmon-exciton polaritons in hybrid structures consisting of a two-dimensional (2D) transition metal dichalcogenide (TMDC) deposited onto a metal substrate or coating a metallic thin-film. We determine the polaritonic spectrum and show that, in the former case, the addition of a top dielectric layer, and, in the latter, the thickness of the metal film,can be used to tune and promote plasmon-exciton interactions well within the strong coupling re…
Electrically driven plasmon-polaritonic bistability in Dirac electron tunneling transistors
Columbia University（哥伦比亚大学）；ETH Zürich（苏黎世联邦理工学院）；National Institute for Materials Science（国立材料研究所）；Air Force Research Laboratory（空军研究实验室）；ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology（巴塞罗那光子科学研究所，巴塞罗那科学技术研究院）；ICREA-Institució Catalana de Recerca i Estudis Avançats（加泰罗尼亚高级研究学院）
We provide an analytical solution to the problem of scattering of electromagnetic radiation by a square-wave grating with a flat graphene sheet on top. We show that for deep groves there is a strong plasmonic response with light absorption in the graphene sheet reaching more than 45%, due to the excitation of surface plasmon-polaritons. The case of grating with a graphene sheet presenting an induced periodic modulation of the conductivity is also discussed.
The plasmon and phonon polaritons of two-dimensional (2d) and van-der-Waals materials have recently gained substantial interest. Unfortunately, they are notoriously hard to observe in linear response because of their strong confinement, low frequency and longitudinal mode symmetry. Here, we propose a fundamentally new approach of harnessing nonlinear resonant scattering that we call stimulated plasmon polariton scattering (SPPS) in analogy to the opto-acoustic stimulated Brillouin scattering (SBS). We show that SPS allows to excite, amplify and detect 2d plasmon and phonon polaritons all acros…
Adjusting the free-electron concentration, the surface plasmon frequency of the semiconductor ZnOGa is tuned into resonance with the molecular vibrations of the n-alkane tetracontane. Closed molecular films deposited on the semiconductor's surface in the monolayer regime generate distinct signatures in total-attenuated-reflection spectra at the frequencies of the symmetric and asymmetric stretching vibrations of the CH2 group. Their line shape undergoes profound changes from absorptive to dispersive and even anti-resonance behavior when moving along the surface- plasmon dispersion by the angel…
A graphene sheet gated with a ridged ground plane, creating a soft-boundary (SB) graphene nanoribbon, is considered. By adjusting the ridge parameters and bias voltage a channel can be created on the graphene which can guide TM surface plasmon polaritons (SPP). Two types of modes are found; fundemental and higher-order modes with no apparent cutoff frequency and with energy distributed over the created channel, and edge modes with energy concen-trated at the soft-boundary edge. Dispersion curves, electric near-field patterns, and current distributions of these modes are determined. Since the l…
We consider a system consists of a doped monolayer phosphorene embedded between two hexagonal Boron Nitride (hBN) slabs along the heterostructure direction. The wavevector azimuthal angle dependence of the plasmon-polariton and plasmon-phonon-polariton modes of the hybrid system are calculated based on the random phase approximation at finite temperature. The collective modes illustrate strong anisotropy and strong coupling with phonon modes of the polar media and furthermore, the Landau damping occurs due to the intraband processes when plasmon enters intraband electron-hole continuum. Our nu…
We consider a biased molecular junction subjected to external time-dependent electromagnetic field. The field for two typical junction geometries (bowtie antennas and metal nanospheres) is calculated within finite-difference time-domain technique. Time-dependent transport and optical response of the junctions is calculated within non-equilibrium Green's function approach expressed in a form convenient for description of multi-level systems. We present numerical results for a two-level (HOMO-LUMO) model, and discuss influence of localized surface plasmon polariton modes on transport.
The condition of phase matching prohibits the transfer of excitation from free-space photons to surface plasmon polaritons (SPP). We propose and analyze a scheme that excites an ensemble of emitters in a collective state, which is phase matched with the SPP by the optical pulses used for its preparation. By a collective enhancement the ensemble, hence, emits an SPP in a well defined direction. We demonstrate the scheme by analyzing the launching of near-infrared graphene SPP. Our theory incorporates the dispersive and dissipative properties of the plasmon modes to evaluate the non-Markovian em…
We provide the quantum mechanical description of the excitation of surface plasmon polaritons on metal surfaces by single-photons. An attenuated-reflection setup is described for the quantum excitation process in which we find remarkably efficient photon-to-surface plasmon wavepacket-transfer. Using a fully quantized treatment of the fields, we introduce the Hamiltonian for their interaction and study the quantum statistics during transfer with and without losses in the metal.
Polaritons are compositional light-matter quasiparticles that have recently enabled remarkable breakthroughs in quantum and nonlinear optics, as well as in material science. Despite the enormous progress, however, a direct nanometer-scale visualization of polaritons has remained an open challenge. Here, we demonstrate that plasmon-exciton polaritons, or plexcitons, generated by a hybrid system composed of an individual silver nanoparticle and a few-layer transition metal dichalcogenide can be spectroscopically mapped with nanometer spatial resolution using electron energy loss spectroscopy in …
In this review we look at the concepts and state-of-the-art concerning the strong coupling of surface plasmon-polariton modes to states associated with quantum emitters such as excitons in J-aggregates, dye molecules and quantum dots. We explore the phenomenon of strong coupling with reference to a number of examples involving electromagnetic fields and matter. We then provide a concise description of the relevant background physics of surface plasmon polaritons. An extensive overview of the historical background and a detailed discussion of more recent relevant experimental advances concernin…
We propose a concept of surface plasmon-polariton amplification in the structure comprising interface between dielectric, metal and asymmetric quantum well. Due to the Rashba spin-orbit interaction, mimina of dispersion relation for electrons in conduction band are shifted with respect to the maximum of dispersion dependence for holes in $Γ$-point. When energy and momentum intervals between extrema in dispersion relations of electrons and holes match dispersion relation of plasmons, indirect radiative transition can amplify the plasmons; excitation of leaky modes is forbidden due to the select…
We consider theoretically surface plasmon polaritons in Weyl semimetals. These materials contain pairs of band touching points - Weyl nodes - with a chiral topological charge, which induces an optical anisotropy and anomalous transport through the chiral anomaly. We show that these effects, which are not present in ordinary metals, have a direct fundamental manifestation in the surface plasmon dispersion. The retarded Weyl surface plasmon dispersion depends on the separation of the Weyl nodes in energy and momentum space. For Weyl semimetals with broken time-reversal symmetry, the distance bet…
