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Evgenii Narimanov

Publications and source records attributed to Evgenii Narimanov.

At least 19 recordsLinked to original sources
arXiv2025

Primordial Media: the shrouded realm of composite materials

Electromagnetic composites (metamaterials) recently underwent explosive growth fueled, in part, by advances in nanofabrication. It is commonly believed that as the size of the components decreases, the behavior of a composite converges to the response of a homogeneous material. Here we show that this intuitive understanding of the electromagnetic response of composite media is fundamentally flawed, even at the qualitative level. In contrast to the well-understood local effective medium response, the properties of nanostructured composites can be dominated by electromagnetic nonlocality. We demonstrate that the interplay between the nonlocality and the structural inhomogeneity introduces two fundamentally new electromagnetic regimes, primordial metamaterials and nonlocal effective medium. We develop an analytical description of these regimes and show that the behavior of metamaterials in the limits of vanishing nonlocality and of vanishing component size do not commute. Our work opens a new dimension in the design space of nanostructured electromagnetic composites.

physics.optics↗
arXiv2021

Confined Hyperbolic Metasurface Modes for Structured Illumination Microscopy

Plasmonic hyperbolic metasurfaces have emerged as an effective platform for manipulating the propagation of light. Here, confined modes on arrays of silver nanoridges that exhibit hyperbolic dispersion are used to demonstrate and model a super-resolution imaging technique based on structured illumination microscopy. A spatial resolution of ~75 nm at 458 nm is demonstrated, which is 3.1 times better than an equivalent diffraction limited image. This work emphasizes the ability to engineer the properties of confined optical modes and to leverage those characteristics for applications in imaging. The results of this work could lead to improved approaches for super-resolution imaging using designed sub-wavelength structures.

physics.optics↗
arXiv2019

Resolution Limit of Label-free Far-field Microscopy

We derive the fundamental limit to the resolution of far-field optical imaging, and demonstrate that, while a bound to the resolution of a fundamental nature does exit, contrary to the conventional wisdom it is neither exactly equal to nor necessarily close to Abbe's estimate. Our approach to imaging resolution that combines the tools from the physics of wave phenomena and the methods of information theory, is general, and can be extended beyond optical microscopy, to e.g. geophysical and ultrasound imaging.

physics.optics↗
arXiv2018

Space-Time Metamaterials

Despite more than a decade of active research, the fundamental problem of material loss remains a major obstacle in fulfilling the promise of the recently emerged fields of metamaterials and plasmonics to bring in revolutionary practical applications. In the present work, we demonstrate that the problem of strong material absorption that is inherent to plasmonic systems and metamaterials based on plasmonic components, can be addressed by utilizing the time dimension. By matching the pulse profile to the actual response of a lossy metamaterial, this approach allows to offset the effect of the material absorption. The existence of the corresponding solution relies on the fundamental property of causality, that relates the absorption in the medium to the variations in the frequency-dependent time delay introduced by the material, via the Kramers-Kronig relations. We demonstrate that the proposed space-time approach can be applied to a broad range of metamaterial-based and plasmonic systems, from hyperbolic media to metal optics and new plasmonic materials.

physics.optics↗
arXiv2017

Dyakonov Waves in Biaxial Anisotropic Crystals

We present the general analytical theory for Dyakonov surface waves at the interface of a biaxial anisotropic dielectric with an isotropic medium. We demonstrate that these surface waves can be divided into todo distinct classes, with qualitatively different spatial behavior. We obtain explicit expressions for the Dyakonov waves dispersion and the parameter range for their existence.

physics.optics↗
arXiv2017

Nonlinear optics at low powers: new mechanism of on-chip optical frequency comb generation

Nonlinear optical effects provide a natural way of light manipulation and interaction, and form the foundation of applied photonics -- from high-speed signal processing and telecommunication, to ultra-high bandwidth interconnects and information processing. However, relatively weak nonlinear response at optical frequencies calls for operation at high optical powers, or boosting efficiency of nonlinear parametric processes by enhancing local field intensity with high quality-factor resonators near cavity resonance, resulting in reduced operational bandwidth and increased loss due to multi-photon absorption. We present an alternative to this conventional approach, with strong nonlinear optical effects at low local intensities, based on period-doubling bifurcations near nonlinear cavity anti-resonance, and apply it to low-power optical comb generation in a silicon chip.

physics.optics↗
arXiv2017

Ghost Waves in Anisotropic Materials: negative refractive index and evanescent field enhancement in lossless media

We show that transparent dielectrics with strong optical anisotropy support a new class of electromagnetic waves that combine the properties of propagating and evanescent fields. These "ghost waves" are created in tangent bifurcations that "annihilate" pairs of positive- and negative-index modes, and represent the optical analogue of the "ghost orbits" in the quantum theory of non-integrable dynamical systems. Similarly to the regular evanescent fields, ghost waves support high transverse wavenumbers, but in addition to the exponential decay show oscillatory behavior in the direction of propagation. Ghost waves can be resonantly coupled to the incident evanescent waves, which then grow exponentially through the anisotropic media - as in the case of negative index materials.As ghost waves are supported by transparent dielectric media, they are free from the "curse" of material loss that is inherent to conventional negative index composites.

physics.optics↗
arXiv2016

Hyper-Structured Illumination

We present a new approach to super-resolution optical imaging, based on structured illumination in hyperbolic media. The proposed system allows for planar geometry, has unlimited field of view, and is robust with respect to optical noise and material losses.

physics.optics↗
arXiv2015

Polarization oscillations of near-field thermal emission

We consider the polarization of thermal emission in the near-field of various materials including dielectrics and metallic systems with resonant surface modes. We find that at thermal equilibrium, the degree of polarization exhibits spatial oscillations with a period of approximately half the optical wavelength, independent of material composition. This result contrasts with that of Setala, Kaivola and Friberg [Phys. Rev. Lett. 88, 123902 (2002)], who find monotonic decay of the degree of polarization for systems in local thermal equilibrium.

physics.optics↗
arXiv2014

Directional out-coupling from active hyperbolic metamaterials

Hyperbolic Metamaterials (HMMs) have recently garnered much attention because they possess the ability for broadband manipulation of the photon density of states and sub-wavelength light confinement. However, a major difficulty arises with the coupling of light out of HMMs due to strong confinement of the electromagnetic field in states with high momentum called high-k modes which become evanescent outside the structure. Here we report the first demonstration of directional out-coupling of light from high-k modes in an active HMM using a high index bulls-eye grating. Quantum dots (QDs) embedded underneath the metamaterial show highly directional emission through the propagation and out-coupling of resonance cones which are a unique feature of hyperbolic media. This demonstration of efficient out-coupling of light from active HMMs could pave the way for developing practical photonic devices using these systems.

physics.optics↗
arXiv2012

Super-resolution Spatial Frequency Differentiation of Nanoscale Particles with a Vibrating Nanograting

We propose a scheme for detecting and differentiating deeply subwavelength particles based on their spatial features. Our approach combines scattering from an ultrasonically modulated nanopatterend grating with heterodyne techniques to enable far-field detection of high spatial frequency Fourier components. Our system is sensitive to spatial features commensurate in size to the patterning scale of the grating. We solve the scattering problem in Born approximation and illustrate the dependence of the signal amplitude at modulation frequency on grating period, which allows to differentiate between model nanoparticles of size $λ/20$.

physics.optics↗
arXiv2012

Super-resolution imaging via spatiotemporal frequency shifting and coherent detection

Diffraction limit is manifested in the loss of high spatial frequency information that results from decay of evanescent waves. As a result, conventional far-field optics yields no information about an object's subwavelength features. Here we propose a novel approach to recovering evanescent waves in the far field, thereby enabling subwavelength-resolved imaging and spatial spectroscopy. Our approach relies on shifting the frequency and the wave vector of near-field components via scattering on acoustic phonons. This process effectively removes the spatial frequency cut-off for unambiguous far field detection. This technique can be adapted for digital holography, making it possible to perform phase-sensitive subwavelength imaging. We discuss the implementation of such a system in the mid-IR and THz bands, with possible extension to other spectral regions.

physics.optics↗
arXiv2011

Broadband Purcell effect: Radiative decay engineering with metamaterials

Engineering the photonic density of states (PDOS) using resonant microcavities or periodic dielectric media gives control over a plethora of classical and quantum phenomena associated with light. Here, we show that nanostructured metamaterials with hyperbolic dispersion, possess a broad bandwidth singularity in the PDOS, an effect not present in any other photonic system, which allows remarkable control over light-matter interactions. A spectacular manifestation of this non-resonant PDOS alteration is the broadband Purcell effect, an enhancement in the spontaneous emission of a light source, which ultimately leads to a device that can efficiently harness a single photon from an isolated emitter. Our approach differs from conventional resonant Purcell effect routes to single photon sources with a limitation in bandwidth, which places restrictions on the probable use of such methods for practical device applications, especially at room temperature. The proposed metadevice, useful for applications from quantum communications to biosensing also opens up the possibility of using metamaterials to probe the quantum electrodynamic properties of atoms and artificial atoms such as quantum dots.

physics.optics↗
arXiv2011

Topological Transitions in Metamaterials

The ideas of mathematical topology play an important role in many aspects of modern physics - from phase transitions to field theory to nonlinear dynamics (Nakahara M (2003) in Geometry, Topology and Physics, ed Brewer DF (IOP Publishing Ltd, Bristol and Philadelphia), Monastryskiy M (1987) in Riemann Topology and Physics, (Birkhauser Verlag AG)). An important example of this is the Lifshitz transition (Lifshitz IM (1960) Anomalies of electron characteristics of a metal in the high-pressure region, Sov Phys JETP 11: 1130-1135), where the transformation of the Fermi surface of a metal from a closed to an open geometry (due to e.g. external pressure) leads to a dramatic effect on the electron magneto-transport (Kosevich AM (2004) Topology and solid-state physics. Low Temp Phys 30: 97-118). Here, we present the optical equivalent of the Lifshitz transition in strongly anisotropic metamaterials. When one of the components of the dielectric permittivity tensor of such a composite changes sign, the corresponding iso-frequency surface transforms from an ellipsoid to a hyperboloid. Since the photonic density of states can be related to the volume enclosed by the iso-frequency surface, such a topological transition in a metamaterial leads to a dramatic change in the photonic density of states, with a resulting effect on every single physical parameter related to the metamaterial - from thermodynamic quantities such as its equilibrium electromagnetic energy to the nonlinear optical response to quantum-electrodynamic effects such as spontaneous emission. In the present paper, we demonstrate the modification of spontaneous light emission from quantum dots placed near the surface of the metamaterial undergoing the topological Lifshitz transition, and present the theoretical description of the effect.

physics.optics↗
arXiv2011

Hyperbolic metamaterial interfaces: Hawking radiation from Rindler horizons and the "end of time"

Extraordinary rays in a hyperbolic metamaterial behave as particle world lines in a three dimensional (2+1) Minkowski spacetime. We analyze electromagnetic field behavior at the boundaries of this effective spacetime depending on the boundary orientation. If the boundary is perpendicular to the space-like direction in the metamaterial, an effective Rindler horizon may be observed which produces Hawking radiation. On the other hand, if the boundary is perpendicular to the time-like direction an unusual physics situation is created, which can be called "the end of time". It appears that in the lossless approximation electromagnetic field diverges at the interface in both situations. Experimental observations of the "end of time" using plasmonic metamaterials confirm this conclusion.

physics.optics↗
arXiv2010

Super-resolution imaging using spatial Fourier transform infrared spectroscopy

Spatial resolution of most imaging devices is fundamentally restricted by diffraction. This limitation is manifested in the loss of high spatial frequency information contained in evanescent waves. As a result, conventional far-field optics yields no information about an object's subwavelength features. Here we propose a novel approach to recovering evanescent waves in the far field, thereby enabling subwavelength-resolved imaging and spatial spectroscopy. Our approach relies on shifting the frequency and the wave vector of near-field components via scattering on acoustic phonons. This process effectively removes the spatial frequency cut-off for unambiguous far field detection. A straightforward extension of this technique, which we call spatial Fourier transform infrared spectroscopy, allows to preserve phase information, making it possible to perform 3D subwavelength imaging. We discuss the implementation of such a system in the mid-IR and THz bands, with possible extension to other spectral regions.

physics.optics↗
arXiv2006

Optical Hyperlens: Far-field imaging beyond the diffraction limit

We propose an approach to far-field optical imaging beyond the diffraction limit. The proposed system allows image magnification, is robust with respect to material losses and can be fabricated by adapting existing metamaterial technologies in a cylindrical geometry.

physics.optics↗