English Phraseology in Teaching: Interrelation of Theory and Practice

AbstractPhraseological units absorb values of the ages in which it lives. The problem of understanding the meaning of a phraseological unit is linked with a possibility of increasing our knowledge about the world diachronically. The authors underline the importance of phraseological studies as it demonstrates the interrelation between the language and the society. The role of phraseological units as specific structures in forming vocabulary and linguacultural competence of students is very significant because they encapsulate a national, country's cultural outlook. Usage-based theories of language learning suggest that phraseology must be studied as a part of vocabulary. Teaching phraseology is a part of cultural approach in foreign teaching methodology and arranging vocabulary studying though structure of component meaning is linguistic approach. This article begins by establishing a theoretical framework to help find the answer to the question: “what do the words in a phraseological unit mean?”. From there, major phraseological concepts on the problem are reviewed. Complex methodology is applied: method of phraseological identification, semantic analysis. Finally, the article concludes with a discussion of four types of word-components in phraseological units: real words; potential words; “former” words; “ghost-words and possible paths for future research

Optical Pulling and Pushing Forces via Bloch Surface Waves

Versatile manipulation of nano- and microobjects underlies the optomechanics and a variety of its applications in biology, medicine, and lab-on-a-chip platforms. For flexible tailoring optical forces, as well as for extraordinary optomechanical effects, additional degrees of freedom should be introduced into the system. Here, we demonstrate that photonic crystals provide a flexible platform for nanoparticles optical manipulation due to both Bloch surface waves (BSWs) and the complex character of the reflection coefficient paving a way for complex optomechanical interactions control. We demonstrate that appearance of enhanced pulling and pushing transversal optical forces acting on a single bead placed above a one-dimensional photonic crystal due to directional excitation of Bloch surface wave at the photonic crystal interface. Our theoretical results, which are supported with numerical simulations, demonstrate angle or wavelength assisted switching between BSW-induced optical pulling and pushing forces. Easy-to-fabricate for any desired spectral range photonic crystals are shown to be prospective for precise optical sorting of nanoparticles, especially for core-shell nanoparticles, which are difficult to sort with conventional optomechanical methods. Our approach opens opportunities for novel optical manipulation schemes and platforms and enhanced light-matter interaction in optical trapping setups

Optical binding via surface plasmon polariton interference

[EN] Optical binding allows creation of mechanically stable nanoparticle configurations owing to formation of self-consistent optical trapping potentials. While the classical diffraction limit prevents achieving deeply subwavelength arrangements, auxiliary nanostructures enable tailoring optical forces via additional interaction channels. Here, a dimer configuration next to a metal surface was analyzed in detail and the contribution of surface plasmon polariton waves was found to govern the interaction dynamics. It is shown that the interaction channel, mediated by resonant surface waves, enables achieving subwavelength stable dimers. Furthermore, the vectorial structure of surface modes allows binding between two dipole nanoparticles along the direction of their dipole moments, contrary to vacuum binding, where a stable configuration is formed in the direction perpendicular to the polarization of the dipole moments. In addition, the enhancement by one order of magnitude of the optical binding stiffness is predicted owing to the surface plasmon polariton interaction channel. These phenomena pave the way for developing new flexible optical manipulators, allowing for control over a nanoparticle trajectory on subwavelength scales and opening opportunities for optical-induced anisotropic (i.e., with different periods along the field polarization as well as perpendicular to it) organization of particles on a plasmonic substrate.The authors acknowledge the support of the Russian Foundation for Basic Research (Grants No. 16-32-60167, No. 18-02-00414, No. 18-29-20063, and No. 18-52-00005). M.I.P. also acknowledges the support from the BASIS Foundation. A.S. acknowledges the support of the Ministry of Education and Science of the Russian Federation (GOSZADANIE, Grant No. 3.4982.2017/6.7). The force calculations were partially supported by Russian Science Foundation (Grant No. 18-72-10127). M.N.-V. is supported by the Spanish MINECO Grants No. FIS2012-36113-C03-03, No. FIS2014-55563-REDC, and No. FIS2015-69295-C3-1-P