In the last 30 days

• Open/close Photonic crystal fibres in biomedical investigations

  Yu S Skibina et al 2011 Quantum Electron. 41 284 Tag this article

  Article References Full text PDF (4.01 MB)

  The state of the art in the field of design and study of photonic crystal fibres for biomedical applications is considered and some original results recently obtained by the authors are presented. Optical properties of the fibres that offer prospects of their wide application as biological sensors, 'labs-on-a-chip', and facilities of electromagnetic radiation control in a wide range of wavelengths aimed at designing novel biomedical instrumentation are considered

• Open/close Solitons in nonlinear optics

  Andrei I Maimistov 2010 Quantum Electron. 40 756 Tag this article

  Article References Full text PDF (638 KB)

  The classic examples of optical phenomena resulting in the appearance of solitons are self-focusing, self-induced transparency, and parametric three-wave interaction. To date, the list of the fields of nonlinear optics and models where solitons play an important role has significantly expanded. Now long-lived or stable solitary waves are called solitons, including, for example, dissipative, gap, parametric, and topological solitons. This review considers nonlinear optics models giving rise to the appearance of solitons in a narrow sense: solitary waves corresponding to the solutions of completely integrable systems of equations basic for the models being discussed.

• Open/close Optics and biophotonics of nanoparticles with a plasmon resonance

  N G Khlebtsov 2008 Quantum Electron. 38 504 Tag this article

  Article References Full text PDF (628 KB)

  A brief review of the state of the art in theoretical and experimental studies of the optical properties of metal particles with dipole and multipole plasmon resonances is presented. Metal spheres, nanorods, spherical and elliptic metal nanoshells are considered. The tuning of plasmon resonances of nanoparticles by varying their size, shape, structure, and dielectric environment is described. A large amount of spectrophotometric data on dimensional characteristics of gold colloidal particles is critically analysed and a new calibration of the dependence of their average size on the extinction plasmon resonance wavelength is proposed. A drastic difference between gold and silver colloids in the region of small deviations of their form from spherical is discussed. An example of the excess over not only the Rayleigh limit for the scattering depolarisation factor for dielectric needles (1/3) but also over the plasmon-resonance limit for metal thin rods (3/4) is presented for the first time. The multipole properties of nanorods and universal linear wavelength scaling of multipole resonances are considered depending on the axial ratio of nanoparticles. The outlook for modern trends in biomedical applications of nanoparticles with plasmon resonances is discussed.
• Open/close Whispering-gallery waves

  Anatolii N Oraevsky 2002 Quantum Electron. 32 377 Tag this article

  Article References Full text PDF (2.18 MB)

  A review of the theory of the natural waves (eigen-modes) in a dielectric sphere is presented. A special attention is paid to the eigenmodes with large radial and azimuthal indices, the so-called whispering-gallery modes. The experimental results of the spectroscopic study of modes in a dielectric sphere are reported. The fields of applications of whispering-gallery modes are discussed.

• Open/close Determination of photophysical parameters of chlorophyll α in photosynthetic organisms using the method of nonlinear laser fluorimetry

  T S Gostev and V V Fadeev 2011 Quantum Electron. 41 414 Tag this article

  Article References Full text PDF (243 KB)

  We study the possibility of solving the multiparameter inverse problem of nonlinear laser fluorimetry of molecular systems with high local concentration of fluorophores (by the example of chlorophyll α molecules in photosynthetic organisms). The algorithms are proposed that allow determination of up to four photophysical parameters of chlorophyll α from the experimental fluorescence saturation curves. The uniqueness and stability of the inverse problem solution obtained using the proposed algorithms were assessed numerically. The laser spectrometer, designed in the course of carrying out the work and aimed at nonlinear laser fluorimetry in the quasi-stationary and nonstationary excitation regimes is described. The algorithms, proposed in this paper, are tested on pure cultures of microalgae Chlorella pyrenoidosa and Chlamydomonas reinhardtii under different functional conditions.

• Open/close Efficient wide-aperture neodymium glass rod amplifiers

  A K Potemkin et al 2011 Quantum Electron. 41 487 Tag this article

  Article References Full text PDF (960 KB)

  Amplifiers based on neodymium phosphate glass rods 60 — 100 mm in diameter are experimentally studied. The amplifiers are pumped by INP-16/250 tubular flash lamps placed in a universal pump cavity with a two-section mirror reflector. A compact high-voltage capacitive energy storage with a preionisation circuit was developed to supply the lamps.

• Open/close Intensity clamping in the filament of femtosecond laser radiation

  V P Kandidov et al 2011 Quantum Electron. 41 382 Tag this article

  Article References Full text PDF (225 KB)

  We have studied numerically the evolution of the light field intensity and induced refractive index of a medium upon filamentation of femtosecond laser radiation in air. It is shown that the intensity clamping results from the dynamic balance of optical powers of nonlinear lenses, induced by radiation due to the Kerr nonlinearity of air, and laser plasma produced during photoionisation. We have found the relation between the peak values of the light field intensity and the electron density in laser-produced plasma, as well as the transverse sizes of the filament and the plasma channel.

• Open/close Fractional laser microablation of skin aimed at enhancing its permeability for nanoparticles

  Elina A Genina et al 2011 Quantum Electron. 41 396 Tag this article

  Article References Full text PDF (817 KB)

  A new method for delivering nanoparticles into the skin using the fractional laser microablation of its surface and the ultrasonic treatment is proposed. As a result of in vitro and in vivo studies, it is shown that the 290-nm laser pulses with the energy from 0.5 to 3.0 J provide the penetration of nanoparticles of titanium dioxide with the diameter ~100 nm from the skin surface to the depth, varying from 150 to 400 μm. Histological testing of the skin areas, subjected to the treatment, shows that the particles stay in the dermis at the depth up to 400 μm no less than for three weeks.

• Open/close Statistics of errors in fibre communication lines with a phase-modulation format and optical phase conjugation

  Elena G Shapiro and Mikhail P Fedoruk 2011 Quantum Electron. 41 541 Tag this article

  Article References Full text PDF (156 KB)

  Analytical formulas are derived to approximate the probability density functions of 'zero' and 'one' bits in a linear communication channel with a binary format of optical signal phase modulation. Direct numerical simulation of the propagation of optical pulses in a communication line with optical phase conjugation is performed. The results of the numerical simulation are in good agreement with the analytical approximation.

• Open/close Second-order Bragg gratings in single-mode chalcogenide fibres

  M Bernier et al 2011 Quantum Electron. 41 465 Tag this article

  Article References Full text PDF (239 KB)

  Bragg gratings with a second-order resonance wavelength in the near-IR spectral region have been inscribed into single-mode chalcogenide (As ₂S ₃) glass fibre by a He — Ne laser beam using a configuration typical of Bragg grating fabrication in germanosilicate fibre, with the use of a phase mask that ensures effective diffraction of the writing light into the +1 and -1 orders. The spectra of the inscribed gratings show no resonances due to cladding mode excitation because the cladding material is photosensitive.