Sergey A. Myslivets

Four-wave mixing, quantum control, and compensating losses in doped negative-index photonic metamaterials

The possibility of compensating absorption in negative-index metamaterials (NIMs) doped by resonant nonlinear-optical centers is shown. The role of quantum interference and the extraordinary properties of four-wave parametric amplification of counterpropagating electromagnetic waves in NIMs are discussed.

Transformable broad-band transparency and amplification in negative-index films

The possibility to produce laser-induced optical transparency of a metamaterial slab through the entire negative-index frequency domain is shown above a certain control laser field intensity threshold.

Nonlinear interference effects and all-optical switching in optically dense inhomogeneously broadened media

Specific features of nonlinear interference processes at quantum transitions in near- and fully-resonant optically-dense Doppler-broadened medium are studied. The feasibility of overcoming of the fundamental limitation on a velocity-interval of resonantly coupled molecules imposed by the Doppler effect is shown based on quantum coherence. This increases the efficiency of nonlinear-optical processes in atomic and molecular gases that possess the most narrow and strongest resonances. The possibility of all-optical switching of the medium to opaque or, alternatively, to absolutely transparent, or even to strongly-amplifying states is explored, which is controlled by a small variation of two driving radiations. The required intensities of the control fields are shown to be typical for cw lasers. These effects are associated with four-wave mixing accompanied by Stokes gain and by their interference in fully- and near-resonant optically-dense far-from-degenerate double-Lambda medium. Optimum conditions for inversionless amplification of short-wavelength radiation above the oscillation threshold at the expense of the longer-wavelength control fields, as well as for Raman gain of the generated idle infrared radiation, are investigated. The outcomes are illustrated with numerical simulations applied to sodium dimer vapor. Similar schemes can be realized in doped solids and in fiber optics.

Negative group velocity and three-wave mixing in dielectric crystals

We investigate extraordinary features of optical parametric amplification of Stokes electromagnetic waves that originate from the three-wave mixing of a backward phonon wave with negative group velocity and two ordinary electromagnetic waves. Such properties were earlier shown to exist only in plasmonic negative-index metamaterials that are very challenging to fabricate. Nonlinear optical photonic devices with properties similar to those predicted for negative-index metamaterials are proposed.

Coherent nonlinear optics and quantum control in negative-index metamaterials

The extraordinary properties of laser-induced transparency of a negative-index slab and parametric amplification for a backward wave signal are investigated. The effects of the idler absorption and phase mismatch on the amplification of the signal are studied, and the feasibility of ensuring robust transparency for a broad range of control field intensities and slab thicknesses is shown. A particular option consisting of the independent engineering of a strong four-wave mixing response and the negative refractive index is proposed and its specific features are investigated. The feasibility of quantum control over the slab transparency in such a scheme is confirmed through numerical experiments. We thus show opportunities and conditions for the compensation of the strong absorption inherent to plasmonic negative-index metamaterials, and we further show achievable transparency through coherent energy transfer from the control optical field to the negative-index signal.

Nonlinear-optical vacuum ultraviolet generation at maximum atomic coherence controlled by a laser-induced Stark chirp of two-photon resonance

A novel scheme is analyzed for efficient generation of vacuum ultraviolet radiation through four-wave mixing processes assisted by the Stark chirp of two photon resonance. In this three-laser technique, a delayed-pulse of strong off-resonant infrared radiation sweeps the laser-induced Stark shift of a two-photon transition and facilitates maximum two-photon coherence induced by the second ultraviolet laser. A judiciously delayed third pulse beats with this coherence and generates short-wavelength radiation. A numerical simulation of transient processes, which ensure maximum coherence, including those leading to Stark-chirped rapid adiabatic passage, is presented. Potential high power and energy conversion efficiency of the weak long-wavelength radiation to the VUV range is shown for a difference-frequency scheme based on parametric amplification of this signal and strong four-wave coupling at maximum atomic coherence.

Nonlinear Optics with Backward Waves: Extraordinary Features, Materials and Applications

Extraordinary properties of nonlinear-optical propagation processes are investigated that involve electromagnetic or elastic waves with negative group velocity. Nanostructured materials that support such waves and prospective unique photonic devices are described.

Inversionless gain in an optically-dense resonant Doppler-broadened medium

Resonant nonlinear-optical interference processes in four-level Doppler-broadened media are studied. Specific features of amplification and optical switching of short-wavelength radiation in a strongly-absorbing resonant gas under coherent quantum control with two longer wavelength radiations, are investigated. The major outcomes are illustrated with virtual experiments aimed at inversionless short-wavelength amplification, which also address deficiencies in this regard in recent experiments. With numerical simulations related to the proposed experiment in optically-dense sodium dimer vapor, we show optimal condition for optical switching and the expected gain of the probe radiation, which is above the oscillation threshold.

Unidirectional amplification and shaping of optical pulses by three-wave mixing with negative phonons

A possibility to greatly enhance frequency-conversion efficiency of stimulated Raman scattering is shown by making use of extraordinary properties of three-wave mixing of ordinary and backward waves. Such processes are commonly attributed to negative-index plasmonic metamaterials. This work demonstrates the possibility to replace such metamaterials that are very challenging to engineer by readily available crystals which support elastic waves with contra-directed phase and group velocities. The main goal of this work was to investigate specific properties of indicated nonlinear optical process in short-pulse regime and to show that it enables elimination of fundamental detrimental effect of fast damping of optical phonons on the process concerned. Among the applications is the possibility of creation of a family of unique photonic devices such as unidirectional Raman amplifiers and femtosecond pulse shapers with greatly improved operational properties.

Nonlinear backward-wave photonic metamaterials

Novel concepts of nonlinear-optical (NLO) photonic metamaterial are proposed. They concern photonic materials that support backward electromagnetic or vibration waves (BWs) and provide coherent nonlinear-optical energy exchange between ordinary and BWs as applied to three- and four-wave mixing processes. Three different classes of materials which support BWs are considered: plasmonic negative-index (NI) metamaterials (NIMs), metamaterials with specially engineered spatial dispersion of the nanoscopic building blocks, such as standing carbon nanotubes, and crystals that support optical phonons with negative group velocity. The possibility to exploit ordinary crystals instead of plasmonic NLO metamaterials that are very challenging to engineer is proposed. It is shown that extraordinary nonlinear optical frequency-conversion propagation processes attributed to NIMs can be mimicked in the proposed metamaterials. It is also shown that the detrimental effects of strong losses can be mitigated in the short-pulse regimes, which exhibit exotic properties when ordinary and BWs are involved in the NLO coupling. Comparative review of unparallel properties of coherent energy exchange between ordinary and backward electromagnetic waves in NIMs and between ordinary electromagnetic waves coupled through backward vibration waves is given. Unique photonic devices are proposed.