One-dimensional long-range plasmonic-photonic structures.

We have fabricated line gratings from periodically etched fused silica on which a thin silver film is deposited that is in turn covered with a silica index-matched fluid. This dielectrically symmetric geometry supports an independent long-range surface plasmon-polariton (LRSPP) and a short-range surface plasmon polariton, and the associated plasmonic band structure has been probed. Coupling to external light is achieved via the patterned grating, and an ultrasharp LRSPP linewidth of 4 nm is observed. The experimental results are compared with finite-difference time-domain simulations.

Perfect coupling of light to surface plasmons with ultra-narrow linewidths.

We examine the coupling of electromagnetic waves incident normal to a thin silver film that forms an oscillatory grating embedded between two otherwise uniform, semi-infinite half spaces. Two grating structures are considered, in one of which the midpoint of the Ag film remains fixed whereas the thickness varies sinusoidally, while in the other the mid point oscillates sinusoidally whereas the film thickness remains fixed. On reducing the light wavelength from the long wavelength limit, we encounter signatures in the transmission, T, and reflection, R, coefficients associated with: (i) the short-range surface plasmon mode, (ii) the long-range surface plasmon mode, and (iii) electromagnetic diffraction tangent to the grating. The first two features can be regarded as generalized (plasmon) Wood's anomalies whereas the third is the first-order conventional (electromagnetic) Wood's anomaly. The energy density at the film surface is enhanced for wavelengths corresponding to these three anomalies, particularly for the long-range plasmon mode in thin films. When exciting the silver film with a pair of waves incident from opposite directions, we find that by adjusting the grating oscillation amplitude and fixing the relative phase of the incoming waves to be even or odd, T+R can be made to vanish for one or the other of the plasmon modes; this corresponds to perfect coupling (impedance matching in the language of electrical engineering) between the incoming light and these modes.

Surface quality and surface waves on subwavelength-structured silver films.

We analyze the physical-chemical surface properties of single-slit, single-groove subwavelength-structured silver films with high-resolution transmission electron microscopy and calculate exact solutions to Maxwell's equations corresponding to recent far-field interferometry experiments using these structures. Contrary to a recent suggestion the surface analysis shows that the silver films are free of detectable contaminants. The finite-difference time-domain calculations, in excellent agreement with experiment, show a rapid fringe amplitude decrease in the near zone (slit-groove distance out to 3-4 wavelengths). Extrapolation to slit-groove distances beyond the near zone shows that the surface wave evolves to the expected bound surface plasmon polariton (SPP). Fourier analysis of these results indicates the presence of a distribution of transient, evanescent modes around the SPP that dephase and dissipate as the surface wave evolves from the near to the far zone.

[Thermography in the complex examination of patients with temporomandibular joint diseases]. / Teplovidenie v kompleksnom obsledovanii bol'nykh s zabolevaniiami visochno-nizhnecheliustnogo sustava.

The authors describe the usage of thermovisual investigation for diagnostic and treatment control purposes in patients with the temporomandibular joint pathology. In chronic arthritis exacerbations, traumatic arthritis and arthroses the joint thermographic images are different. Thermometry was performed at distinct points of parotidmusticulatory, submandibular and cervical regions. Normal and pathological thermal gradients were found between symmetrical facial sites.

[The deformation-strain state of bridgework dentures]. / Issledovanie napriazhenno-deformirovannogo sostoianiia mostovidnykh protezov.

Holographic interferometry was used to study strained deformed status of bridge dentures. The technique of measurements with a small holographic system is described. Dentures made of Cr-Ni steel with a principally new method of crown to intermediate part adhesion were under study, as were other bridge denture designs. The findings evidence that holographic interferometry may be used as a sparing method for checking up the quality of casting and adhesion of abutment crowns and an intermediate part of fixed dentures, as well as the strength of adhesion of the facing material (porcelain, plastic) to the metal base of the denture.

[The results of using Unifas cement for denture fixation]. / Rezul'taty primeneniia tsementa "Unifas" dlia fiksatsii zubnykh protezov.

Unifas cement was used for fixation of cermet dentures in 104 patients. Clinical follow-up of 3 months to 3 years duration demonstrated sufficiently high adhesive characteristics, resistance to oral fluid and mechanic loading effects of this cement, which is recommended for wide clinical practice.

Electrostrictive response in single-mode ring-index-profile fibers.

We have theoretically investigated, for what is to our knowledge the first time, the electrostrictive response in a single-mode ring-core fiber. We found that the electrostrictive response function differs strongly from those of standard fibers with a Gaussian light-intensity profile.