Showing papers by "Viktor A. Podolskiy published in 2005"
TL;DR: In this article, an anisotropic dielectric constant is used to provide a lefthanded behavior in waveguide geometry for optical and infrared waveguide applications, and the connection between the polaritons and the enhancement of evanescent fields is demonstrated.
Abstract: We develop an approach to build a material with negative refraction index that can be implemented for optical and infrared frequencies. In contrast to conventional designs that require simultaneously negative dielectric permittivity and magnetic permeability and rely on a resonance to achieve a nonzero magnetic response, our material is intrinsically nonmagnetic and makes use of an anisotropic dielectric constant to provide a lefthanded behavior in waveguide geometry. We demonstrate that the proposed material can support surface (polariton) waves, and show the connection between the polaritons and the enhancement of evanescent fields, also known as superlensing.
322 citations
TL;DR: In this paper, the authors consider the problem of subwavelength imaging via a slab of a left-handed medium (LHM) in the presence of material losses and derive the analytical expression for the resolution limit of a LHM-based lens and demonstrate that the area of its sub-wavelength performance is usually limited to the near-field zone.
Abstract: We consider the problem of subwavelength imaging via a slab of a left-handed medium (LHM) in the presence of material losses. We derive the analytical expression for the resolution limit of a LHM-based lens and demonstrate that the area of its subwavelength performance is usually limited to the near-field zone.
248 citations
TL;DR: Nicorovici et al. as mentioned in this paper showed that a cylindrical superlens can successfully image a dipole line source in the limit as the loss in the lens tends to zero.
Abstract: Enlarging upon work of Nicorovici, McPhedran & Milton ([Nicorovici et al . 1994][1] Phys. Rev. B 49 (12), 8479–8482), a rigorous proof is given that in the quasistatic regime a cylindrical superlens can successfully image a dipole line source in the limit as the loss in the lens tends to zero. In this limit it is proved that the field magnitude diverges to infinity in two sometimes overlapping annular anomalously locally resonant regions, one of which extends inside the lens and the other of which extends outside the lens. The wavelength of the oscillations in the locally resonant regimes is set by the geometry and the loss, and goes to zero as the loss goes to zero. If the object or source being imaged responds to an applied field it is argued that it must lie outside the resonant regions to be successfully imaged. If the image is being probed it is argued that the resonant regions created by the probe should not surround the tip of the probe. These conditions taken together make it difficult to directly probe the potential in the near vicinity of the image of a source or object having small extent. The corresponding quasistatic results for the slab lens are also derived. If the source is too close to the slab lens, i.e. lying within the resonant region, then the power dissipation in the lens tends to infinity as the loss goes to zero, which makes the lens impractical for imaging such quasistatic sources. Perfect imaging in a cylindrical superlens is shown to extend to the static equations of magnetoelectricity or thermoelectricity, provided they have a special structure which makes these equations equivalent to the quasistatic equations.
[1]: #ref-22
161 citations
TL;DR: In this paper, the optical response of isolated nanowires, double-wire systems, and Π-structures is compared in terms of their electric and magnetic dipole moments, and it is shown that both dielectric permittivity and magnetic permeability can be negative at optical and near infrared frequencies.
Abstract: We compare the optical response of isolated nanowires, double-wire systems, and Π-structures, and show that their radiation is well described in terms of their electric and magnetic dipole moments. We also show that both dielectric permittivity and magnetic permeability can be negative at optical and near infrared frequencies, and demonstrate the connection between the geometry of the system and its resonance characteristics. We conclude that plasmonic nanowires can be employed for novel negative-index materials. Finally, we demonstrate that it is possible to construct a nanowire-based 'transparent nanoresonator' with dramatically enhanced intensity and metal concentration below 5%.
105 citations
TL;DR: In this paper, the performance of a planar lens based on realistic negative index material in a generalized geometry was analyzed, and it was shown that the conventional superlens design (where the lens is centered between the object and the image) is not optimal from a resolution point of view.
Abstract: We analyze the performance of a planar lens based on realistic negative index material in a generalized geometry. We demonstrate that the conventional superlens design (where the lens is centered between the object and the image) is not optimal from the resolution point of view, develop an analytical expression for the resolution limit of a generalized lens, use it to find the optimum lens configuration, and calculate the maximum absorption practical nearfield superlenses may have. We demonstrate that in contrast to the conventional superlens picture, planar imaging is typically accompanied by excitation of surface waves at both interfaces of the lens.
69 citations
TL;DR: It is demonstrated that the lifetimes and emission patterns of the optical modes in generic (asymmetric) microresonators are strongly affected by the phenomenon of chaos-assisted tunneling and a theory of the effect is developed.
Abstract: We demonstrate that the lifetimes and emission patterns of the optical modes in generic (asymmetric) microresonators are strongly affected by the phenomenon of chaos-assisted tunneling and develop a theory of the effect.
55 citations
TL;DR: In this paper, the authors demonstrate that non-magnetic (μ≡1) left-handed materials can be effectively used for waveguide imaging systems, and they also propose a specific THz realization of a nonmagnetic lefthanded material based on homogeneous, naturally occurring media.
Abstract: We demonstrate that non-magnetic (μ≡1) left-handed materials can be effectively used for waveguide imaging systems We also propose a specific THz realization of a non-magnetic left-handed material based on homogeneous, naturally occurring media
49 citations
TL;DR: In this paper, the authors demonstrate that non-magnetic left-handed materials can be effectively used for waveguide imaging systems, and they also propose a specific THz realization of the nonmagnetic material based on homogeneous, naturally-occurring media.
Abstract: We demonstrate that non-magnetic ($\mu \equiv 1$) left-handed materials can be effectively used for waveguide imaging systems. We also propose a specific THz realization of the non-magnetic left-handed material based on homogeneous, naturally-occurring media.
35 citations
TL;DR: It is shown that the lasing modes in the devices has dynamical localization origin and should be applicable to any lasers and sensors based on semiconductor or polymer materials.
Abstract: We demonstrate the lasing action from a dynamically localized mode in a microdisk resonator with rough boundary. Although substantial boundary roughness and surface defects in our devices imply strong light scattering and destroy the regular whispering gallery modes, the destructive interference of the scattered light leads to the dynamical Anderson localization in the phase space of the system and the formation of a different type of high-Q modes. Using direct optical imaging of the lasing mode and theoretical calculations, we show that the lasing modes in our devices has dynamical localization origin. This behavior, although demonstrated here in GaAs-InAs microdisk laser, should be applicable to any lasers and sensors based on semiconductor or polymer materials.
14 citations
03 Jul 2005
TL;DR: In this paper, the authors proposed a non-magnetic and homogeneous waveguide with negative phase velocity and refractive index, based on EM wave propagation inside a strongly anisotropic dielectric material in waveguide geometry.
Abstract: Materials with simultaneously negative values of effective dielectric permittivity and magnetic permeability have been shown to have negative phase velocity (and refractive index). We propose a new approach to constructing a system with negative refractive index. In contrast to all previous designs, our system is implicitly non-magnetic and homogeneous. The proposed material is based on EM wave propagation inside a strongly anisotropic dielectric material in waveguide geometry. This design is highly scalable from GHz to optical frequencies. We present the theoretical description of the EM properties of the proposed system and several realizations for different spectral ranges.
1 citations
22 May 2005
TL;DR: In this article, the authors presented several nanoplasmonic composites, having strong anisotropy of dielectric constant at optical frequencies, and developed the corresponding theory.
Abstract: We present several nanoplasmonic composites, having strong anisotropy of dielectric constant at optical frequencies, and develop the corresponding theory. The proposed applications include low-loss optical negative-n materials, filters, and polarizers
TL;DR: In this article, a nanostructured plasmonic composite material was demonstrated to have a negative index of refraction at infrared and optical frequencies, and the analytical description of the relevant electromagnetic phenomena and justify their analytic results via numerical solutions of the Maxwell equations.
Abstract: We demonstrate that a nanostructured plasmonic composite material
can show negative index of refraction at infrared and optical frequencies. In contrast to conventional negative refraction materials, our design does not require periodicity and thus is highly tolerant to fabrication defects. Moreover, since the proposed material is intrinsically non-magnetic (μ ≡ 1), its performance is not limited to proximity of a resonance so that the resulting structure has relatively low loss. We develop the analytical description of the relevant electromagnetic phenomena and justify our analytic results via numerical solutions of Maxwell equations.
TL;DR: In this article, the authors demonstrate that the Dynamical Anderson Localization of light leads to high-Q whispering gallery modes in microcylinder and microdisk resonators with substantial surface roughness, and determine their lifetimes and emission patterns.
Abstract: We demonstrate that the phenomenon of Dynamical Anderson Localization of light leads to high- Q whispering-gallery modes in microcylinder and microdisk resonators with substantial surface roughness, and determines their lifetimes and emission patterns.
22 May 2005
TL;DR: In this paper, a non-magnetic system with negative refraction index for terahertz applications is proposed based on a planar metallic waveguide with bismuth core.
Abstract: We propose a non-magnetic system with negative refraction index for terahertz applications. The system is based on a planar metallic waveguide with bismuth core, and uses strong anisotropy of bismuth permittivity and its ultra-low losses
22 May 2005
TL;DR: In this article, a non-magnetic and scalable approach for systems with negative index of refraction (NIFR) is presented. But the proposed design is non-magnagnetic and scalable from GHz to optical frequencies.
Abstract: We present a new approach to systems with negative index of refraction. The proposed design is non-magnetic and scalable from GHz to optical frequencies. We describe optical properties of the proposed structure and its realizations.
TL;DR: In this paper, an anisotropic dielectric constant is used to provide negative refractive index in waveguide geometry for optical and infrared super-lensing applications, which is not limited to the proximity of a resonance and thus allows for low loss.
Abstract: We develop a new approach to materials with negative refraction index which can be implemented for optical and infrared frequencies. In contrast to conventional designs which require simultaneously negative dielectric permittivity and magnetic permeability, our system is intrinsically non-magnetic and makes use of an anisotropic dielectric constant to provide negative refractive index in waveguide geometry. The proposed approach is not limited to the proximity of a resonance and thus allows for low loss, critical for super-lensing applications.
09 Nov 2005
TL;DR: In this paper, a planar waveguide structure with a strongly anisotropic core can be used as a non-magnetic medium with negative refractive index, where the optical radiation propagating in the plane of the waveguide is effectively confined in deep subwavelength space perpendicular to this plane, leading to an enhancement of energy density inside the system.
Abstract: It has been recently shown that a planar waveguide structure with a strongly anisotropic core can be used as non-magnetic medium with negative refractive index. In such a system, the optical radiation propagating in the plane of the waveguide is effectively confined in deep subwavelength space perpendicular to this plane, leading to the strong enhancement of energy density inside the system. We demonstrate the possibility of using the high energy-density waveguide as a planar lens, present a detailed study of imaging properties of the proposed system, and consider the perspectives of energy confinement beyond the diffraction limit.
22 May 2005
TL;DR: In this paper, a ratchet resonator is proposed to increase the efficiency of light trapping by dynamical localization of resonant modes and broken symmetry between positive and negative angular momenta.
Abstract: We present novel "ratchet" resonators. Due to dynamical localization of resonant modes and broken symmetry between positive and negative angular momenta, these devices show increased efficiency of light trapping and can be used for sensing applications.