RU2239856C2 - Method for receiving surface polaritons - Google Patents

Abstract

FIELD: optics.

SUBSTANCE: method includes directing exciting laser beam at sliding angle no more than 20 degrees, onto surface of liquid or polymer film with thickness no less than 10 micrometers, surfaces of which are covered by molecular layer of polar molecules, or insertion of exciting laser beam into rib of said liquid or polymer film, or insertion of exciting laser beam into end of liquid thread with thickness no less than 10 micrometers and covered by layer of polar molecules. As film or thread film or thread of water solution may be used, covered by layer of molecules of surfactants.

EFFECT: possible production of polaritons in new environments, increased run distance and increased energy concentration.

2 cl, 10 dwg

Description

The invention relates to methods for producing directed surface electromagnetic waves (polaritons) traveling between media along a boundary surface (surfaces).

It is known that surface electromagnetic waves, or surface polaritons, are a special type of macroscopic electromagnetic waves propagating along surfaces (interfaces) of the medium / 1, 2 /. The field of such waves is pressed to the surface and localized mainly in a layer whose dimensions on each side of the boundary are, as a rule, of the order of the wavelength. Such waves are called surface waves in contrast to bulk waves, which propagate in bulk media and do not feel the significant influence of their surfaces.

The conditions for the existence of surface polaritons in the case of contact of isotropic media consist primarily in the fact that the permittivities of the boundary media must have opposite signs, i.e. one of them must be negative. Surface waves are non-radiation waves, they cannot be excited directly with the help of light waves propagating in one of the two media, and their phase velocity is less than the phase velocity of light in the medium. Surface electromagnetic waves have a mixed electromagnetic-mechanical nature associated with the polarization properties of the boundary surfaces.

Surface waves are objects that are extremely interesting in the physical plane, because they carry rich information about the properties of these surfaces, and at present much attention is paid to their preparation and research / 1-5 /.

There are several methods for producing polaritons on the boundary surfaces of metals, crystals, semiconductors, solid-state multilayer structures / 2, p. 71 /. This is the method of external reflection when a laser beam acts on random surface roughnesses or on a periodically profiled surface, the method of impaired total internal reflection through a prism with a gap to the sample surface (Otto geometry), through a prism on the face of which a thin film of the sample is applied (Kretschmann geometry), two prism method and aperture method.

Microwave and visible laser radiation are used to excite polaritons. The mean free paths of polaritons have an inverse-quadratic dependence on the pump radiation frequency, and therefore, in the visible range, the mean free paths of surface waves in the studied samples are negligible (a few microns) / 1, p. 75 /. So in experiments with a wavelength of exciting light of 632.8 nm for the study of polaritons in thin metal films / 5 / (prototype), the mean free path recorded using a near-field optical microscope does not exceed 10 μm. The polaritons were excited in a thin silver film 60 nm thick, placed near the hypotenuse of a rectangular glass prism and illuminated through a prism with a focused beam of polarized laser radiation with a power of 2.2 mW.

Due to the high attenuation and in gases due to the low particle concentration, no polariton radiation is observed in liquids (/ 2 / p.6 “We can speak of polaritons in the case of not only crystals, but also liquids and even gases, however, characteristic manifestations of the mixing effects with individual dipole-active transitions it is more difficult to observe here (in liquids due to high attenuation, in gases - a relatively low concentration of particles of matter, etc. ”).

The disadvantages of the prototype and other known methods for producing polariton radiation include a limited range of solid-state active media capable of supporting surface polariton radiation, the small mean free path of polariton radiation received on them over the surface, the complexity of the known methods for focusing or concentration.

The objective of the invention is to obtain polaritons in new environments, increasing the mean free path and the concentration of their energy.

To solve the problem, i.e. for producing polaritons with a long mean free path, including in the visible range, it is proposed that laser excitation use not homogeneous solid-state, but free layered media in which some layers have a thickness of one molecule, i.e. molecularly layered media in the form of, for example, thin liquid films and filaments with a thickness of less than 10 microns, on the surface (surfaces) of which there is a layer of polar molecules, such as molecules of surface active substances (surfactants). As our studies show, visible laser light (450–700 nm) introduced into such free films leads to the appearance of surface polaritons in them with a range of tens of centimeters and a high energy concentration.

The experimental design is simple. In a transparent volume (or on a frame made of a transparent material) by blowing with air (or dipping the frame into a soap solution), an ordinary flat or slightly convex soap film is created. The forms of the transparent volume (or frame) can be any, but for the convenience of observations, it is better to have film sizes in the range from a few centimeters to tens of centimeters. The thickness of a freshly prepared soap film usually does not exceed 10 microns. The position of the film plane can be any: horizontal, vertical or inclined, but before the experiment, the film is oriented in space so that the laser beam used for excitation lies in the plane of the film. Through the transparent walls of the volume (or frame), a laser beam is directed and introduced into the film through its edge (edge), focused, for example, into a focal spot or strip with a width of about 10 μm. A typical view of our cuvette with a diameter of 65 mm and a length of 25 mm for laser excitation and the study of polaritons in films is shown in Fig. 1. On it, an arrow shows a horizontal and shiny soap film stretched in the middle between the windows of the cuvette. At the bottom of the cuvette, a small portion of a soap solution is visible, from which a soap film is created by blowing. A laser beam of a helium-neon laser with a wavelength of 632.8 nm lying in the plane of the film is introduced into the film by focusing it with a spherical lens with a focal distance F = 10 cm through the window onto the end of the film (edge) located on the window and clearly visible through the transparent window of the cuvette. Similar experiments can be carried out in any other transparent plastic or glass bottles, in which 20-50 cm ^{3 of} soap solution are poured, and large soap bubbles or separate films along the diameter of the bottles are created by shaking or blowing. The experiments can also be carried out with films on a transparent framework in the air, but in this case they live less.

Polariton radiation propagates from the point of entry of the laser beam through the film, which has the following properties:

1. Excitation is carried out by laser radiation (pumping) in a wide frequency range by a beam of cadmium (441.6 nm), helium-neon (632.8 nm), argon (488 and 514 nm), semiconductor (690 nm) lasers with their radiation powers from 1 mW to 3 W or more. Thus, the spectral range of exciting lasers covers the entire visible range and, judging by the proposed mechanism of action, goes beyond it, apparently limiting itself only to the spectral transparency band of the materials used.

2. It is excited in the films when the laser radiation (direct without focusing or focused by a spherical or cylindrical lens) is directed into the film through its transparent edge (edge). The laser beam can be introduced into the film not only through the edge, but also from the side through the air when focusing on individual dust particles on the surface at small moving angles (up to 20 °) to the film.

3. For a more efficient excitation of polaritons, it is preferable that the polarization of the pump radiation be perpendicular to the thin film, but in some films they are excited with equal efficiency even with horizontal polarization. Under the most optimal excitation conditions, according to our estimates, about 1% of the incident pump radiation enters the film, and the rest is scattered, creating a background that prevents the observation.

4. In thin films (about 0.1-0.01 μm, that is, a thickness substantially less than the wavelength of the exciting laser radiation), the surfaces of which weakly reflect visible light incident from the side (in the so-called pre-black and thin black films), polariton radiation is excited particularly efficiently. In the volume of liquids and solutions and on the surfaces of liquids and solutions with surfactants, polariton radiation does not occur under the same conditions of laser excitation.

5. The polariton radiation excited on the surface of the films is detected externally (by the eye or by equipment) by scattering or the fluorescence caused by them, added to the dye solution. Earlier / 1, p.174 / it was already noted that “The scattering of PPW (surface polariton waves) can also occur on inhomogeneities in the bulk of the sample and on fluctuations of the dielectric constant. The scattering intensity value itself contains information about the characteristic dimensions of the roughness. In the presence of roughness, the electromagnetic field of the surface polariton, remaining mostly localized near the surface, can have a radiation component. ”

6. In liquid transparent films, polaritons go directly from the place of excitation along the film in different directions and have a form that is unexpected for a light beam — their energy is self-compressing, concentrated, and travels over long distances (tens of centimeters) in the form of thin (up to submicron), non-diverging, very bright rays of almost constant intensity (whiskers). In FIG. Figure 2 shows the track of polariton radiation coming from the focal point (focused by a spherical lens F = 10 cm onto the edge of a 632.8 nm, 10 mW laser beam film) in a thin (black) soap film 10 cm long, which stood for two days in a cuvette. The laser beam focuses on the edge of the film on the right. In the film, the track is divided into two bundles of very narrow whiskers of almost the same intensity over the entire length, which tremble slightly, get washed out at a high shutter speed and therefore look like two tracks on a black and white photo.

In thicker (1-10 μm) films, the tracks of polariton radiation are often broken (like lightning) with branches (as shown in Fig. 3), which, depending on the uniformity, thickness, composition, and condition of the film, can be thrown (tens of times per second change the direction of his movement before turning 180 °), the intensity of his glow, refract, self-intersect (as shown in Fig. 4), or be saved in the form of a narrow beam of closely spaced whiskers at large distances (Fig.2). The whiskers are equally effective in straight and curved films (with a radius of curvature R = 1-10 cm). In thick films (5-10 μm), the formed whiskers are less bright and significantly wider than in thin films. Polariton radiation may not have branching (as one channel in FIG. 2) in the so-called true black films with a thickness of about 0.005 μm, consisting of only two tightly adjacent monomolecular surfactant layers with virtually no solution layer between them. The films become so black at the last stage of their aging before they break when the solution separates the surface layers of surfactant molecules forming them from the films.

7. It is very characteristic that, for polaritons (in contrast to bulk radiation), films of different thicknesses represent media with different refractive indices. So, for thin films, the refractive index is close to 1 (a laser beam incident in air at an angle on the edge of such a film gives rise to polariton radiation in it, the beam direction of which almost exactly coincides in the direction of the laser beam, i.e., as if the polariton the radiation did not go through the liquid film, but through the air), and in thick films it rises to 1.25-1.28. At the contact boundary of films of different thicknesses, polaritons are sharply refracted and partially reflected from them, as shown in the vertical film in Fig. 5. In Fig. 5, a characteristic trace of the light track of a polariton traveling along a black film (less than 0.06 microns thick) and incident at a small sliding angle to the horizontal border with the underlying gray (about 0.06 microns thick) film is seen from above. In a gray film, the track sharply refracts (60 ° from the normal) and immediately breaks up into dozens of parallel traveling and slightly moving thin polariton whiskers. It is seen that in the gray film the mustache shines much brighter than in black, but due to the movement of the mustache in the photo, they are washed away into a common parallelogram about 1 cm wide. From below, a trail is also illuminated by this mustache at the bottom of the cuvette under the solution. (As you know, the law of the ratio of the sines of the angles of incidence and refraction is also valid for polariton radiation / 2, p.138 /). In films with a smooth change in thickness, the polariton whiskers smoothly bend. Figure 6 shows a view of a mustache of polariton radiation in a vertical film with a thickness varying in height. You can see the tracks of individual whiskers and their bend in the film, similar to the movement of a scattering water stream in the air.

Polaritons are especially efficiently excited when the direction of pumping through the film (or laterally through the air at a sliding angle of not more than 20 ° to the film) is to a spontaneously arising sharp boundary between the black and more reflecting pre-black (gray) films that is usually clearly visible in reflected light (as in FIG. 5). Focusing the pump above and below this boundary does not produce any whiskers in the film. In the case where the vertical film has lower contact with the solution from which it is drawn, polaritons in the film can be excited by a laser beam from below from the solution, but only when it goes in the plane of the film and falls from below to the solution – film interface at an angle of about 50 -52 ° (or less) from normal. The beam of polariton whiskers formed in this case is in the film almost parallel to the contact interface. At incidence angles exceeding this critical angle, laser radiation does not enter the film from the solution.

8. At the exit of surface radiation (whiskers) through the transparent boundary edges of the films (or in the middle of the films on dust particles) into the air or into the solution, the thin whiskers of polaritons are refracted, converted, and acquire noticeable angular divergence, as is the case with volume radiation with a pump wavelength. They interfere and give a ruled constantly flashing structure of light and dark thin stripes on the screen, as shown in Fig.7, located at a distance of 25 cm from the film. Cells on the screen of 5 mm. Due to the constant movements and blinking of the strips, their width visible by the eye is about an order of magnitude narrower than in the photo.

The brightness of the light tracks in the solution from the whiskers emerging from the film (due to the divergence) is noticeably lower than in the film.

9. When excited by a single laser beam, but at two wavelengths (488 and 514 nm), the whiskers of polaritons observed in transparent films can simultaneously have different colors (blue or green). Fig. 8 shows a polariton whiskers in a horizontal film when excited by a focused spherical lens (F = 10 cm) by argon laser radiation (488 and 514 nm, 3 W). In such a stream, the film lives for several tens of seconds.

10. The number of tracks (modes) of polariton radiation simultaneously excited in the films can reach many tens, as can be seen in Fig. 9, which shows the splitting of polariton radiation in a vertical film into individual tracks (modes) of whiskers in a 10-cm cuvette. Pumping is carried out to the right through the edge of the film with a focused spherical lens (F = 10 cm) laser radiation (632.8 nm, 10 mW). The structure of the modes, their coupling with the film, and losses can be as diverse as that of surface modes calculated for thin metal films / 6 /. When polaritons are excited on one film by two closely spaced or intersecting laser beams (632.8 nm, 10 mW each), there is no noticeable effect of intersecting whiskers from different lasers on each other.

11. As films for the production of polaritons, you can use soap films from a transparent aqueous solution of almost any ordinary soap with and without additives, shampoo or surfactant, at almost any concentration capable of forming films in air. The nature of the behavior of whiskers, their appearance, as well as the lifetime of the films (from seconds to weeks), depend on the viscosity of the solution, the type of surfactant molecules, their concentration and differs significantly, for example, for surfactants such as sodium dodecyl sulfate (SDS) and Triton X- 100. In thin 3-5 micron solid-state films of mica, polyethylene and teflon, under similar conditions of laser excitation, polariton whiskers are not formed.

12. In films from turbid solutions with a large number of scattering centers, in bulk solutions of which the laser beam is scattered and visible at a distance of about 1 cm (under excitation conditions identical with films from transparent solutions) polariton whiskers appear very branched, with a wide near the trees, a crown of very thin mustaches.

13. In films with laser light absorbers (such as dyes), in bulk solutions of which the laser beam is absorbed at a distance of about 1 cm, polariton radiation is excited and thin whiskers in them propagate over distances 5-10 times larger as the films age and decrease than in the volume of the same solution.

14. The ambient temperature has little effect on the nature and behavior of the whiskers in the films, which are observed at all room temperatures from 0 to 30 ° C.

15. The whisker throwing speed in the film increases sharply, and the mean free path decreases sharply if there is a mist of droplets from supersaturated water vapor in the air surrounding the film that settle on the film.

16. The same polaritons as in the films, judging by the scintillation of the output radiation in a wide angle with a solution of about 90 °, are formed by laser irradiation from the end of thin liquid filaments (ribs), which naturally form when two bubbles contact at the junction of three films and possess waveguide properties (figure 10). These filaments live for days and become very thin (50-5 nm) in the vicinity of black films.

17. If we direct focused laser radiation with vertical (parallel to the film) polarization to the side of a freshly prepared vertical film at a side angle of less than 20 °, then most of the beam (90-95%) from the film is reflected and a small part (about 5-10%) passes through the film. The whisker tracks in the film spontaneously arise only when a random speck of dust appears in the focusing area of the film. Moreover, during the existence of a polariton whiskers on the film, the intensity of light passing through the film increases several times, and its polarization (in contrast to the pump beam) is perpendicular to the film.

18. As experiments with mechanical interruption of the laser pump beam show, the formation time of whiskers in films with a helium-neon laser with a power of 5-10 mW is shorter than 10-4 s.

The listed features show that polariton radiation in liquid films and filaments has a number of significant features that distinguish them from both bulk and previously known / 1-5 / polariton radiation on the surfaces of solids.

The theory of polaritons in liquid composite molecular layered films has not yet been developed, and the possibilities of their preparation in such films have not been discussed. There is reason to believe that closely located and separated by a solution monomolecular surfactant layers, representing two-dimensional crystals that are densely or not, play a significant role in the excitation of such polaritons, in the self-compression and concentration of their energy and the formation of narrow directional tracks (whiskers) very tightly packed polar molecules bounding the surface of the films. The polarization and additional interaction of these layers (such as mutual polarization enhancement) induced by laser radiation cause changes in the properties of the films, the formation of polaritons in the films and the concentration of their energy in a thin mustache. A change in the power of the used laser pump radiation by more than 3000 times (from 1 mW to 3 W), as can be seen in Fig. 3 and Fig. 8, has little effect on the form and nature of the behavior of the whiskers in the films.

It is clear that with this mechanism of action, the layer separating surfactant monolayers can be not only water, but also a different solvent (we observed polariton whiskers in a solution of Triton X-405 in kerosene) that can create films with polar molecules on the surface, as well as a polymer component in similar in properties to polymer films and threads with layers of polar molecules on their surfaces.

The constant throwing of a thin whiskers is caused by minute inhomogeneities of the medium and flows in it, heating and the influence of light pressure concentrated in a thin mustache of radiation on a liquid, easily deformable and mobile medium with an extremely small mass. The direction of the whiskers can be controlled by changing the direction of the pump beam and by introducing a controlled optical inhomogeneity into the film along the path of the whisker (or right above the film). It is possible to change the direction of polariton radiation from a filament by mechanically changing its orientation.

Example 1. In a cuvette with a diameter of 6 cm and a length of 10 cm with transparent windows, a transparent (1-10)% solution of the Triton X-100 compound in water is poured into water and blowing or lifting from the solution frame create a vertical soap film between the windows in it. The fresh film has a thickness of about 10 μm, which decreases as the solution swells, as seen in reflected daylight by the number of horizontal interference fringes on the film. Radiation of a He-Ne laser (632.8 nm, 10 mW) with a polarization perpendicular to the film is directed to the lateral surface of the transparent edge (edge) of the film, which is located on the inner surface of the transparent window of the cuvette, focused on a spherical lens (F = 10 cm). Angular adjustment of the visible laser beam, carried out with an accuracy of several degrees, ensures that the largest part of the laser radiation falls on the center of the rib and enters the film from the rib. With this setting, filamentous, brightly luminous, mobile, multi-centimeter light channels of polariton radiation appear in the film directly from the focal point, which are especially clearly visible through the exit window of the cell (Fig. 9), with the properties described above. Moving the focal point vertically along the edge, it is possible to change the direction of the mustache beam emerging from the focal point in a small angular interval.

Almost the same result is obtained with other Triton X-100 concentrations and using even and curved soap films from any other soap solutions and other pump lasers with radiation powers sufficient to detect radiation in the films (usually above 1 mW).

Example 2. In a cuvette with a diameter of 6 cm and a length of 2.5 cm with transparent windows, a (1-10)% solution of the Triton X-100 compound is poured in water and two soap bubbles are inflated on both sides so that they touch each other friend and create an edge at the contact boundary of three films (between the windows of the cell). Several such ribs can be seen in figure 1 to the left of the film stretched in the middle of the cuvette. The He-Ne laser radiation (632.8 nm, 10 mW) focused by a spherical lens (F = 10 cm) is directed to the transparent end face of this filiform rib, which is located between the transparent windows of the cuvette. Carried out with an accuracy of several degrees, the angular adjustment of the visible laser beam is achieved so that the largest part of the laser radiation falls on the center of the edge of the rib and comes into it. With this setting, the side surface of the rib begins to glow brightly, and at the exit from the rib, a bright central spot with a divergence of about 0.1 and a blotchy spot surrounding it with an angular divergence of about 90 ° appear on the screen, indicating that the trajectory of the whiskers in the thread and the polariton character are throwing received in the edge of radiation. Figure 10 shows a cuvette with a thread (rib) from a soap solution (between three black films) 2.5 cm long and the type of laser radiation transmitted through it (632.8 nm, 10 mW) on the screen. The spotted region around the bright central spot constantly blinks like a pattern of bands from the polariton whiskers in Fig. 7. As the solution drains, the blink rate decreases, but the appearance of the output radiation pattern on the screen with a wide spotted field persists for many days. In this case, the thickness of the rib decreases, and when the thickness of the rib is comparable with the thickness of the black film (ten times smaller than the wavelength of the laser radiation), polariton radiation directed at an angle to the edge along the black film bordering it does not reflect from the edge, but reradiates them in the form of a cone of rays and mustaches in adjacent films.

Almost the same result is obtained at other concentrations and using straight and curved soap threads (ribs) from any other soap solutions and other pump lasers.

Example 3. Across an open glass with a diameter of 6 cm, a thin (less than 10 μm) film is pulled from the one described in http://www.iluvcats.com/buforpe.htmi,

http: //pubs.acs. org / cenAvhatstuff / stufT / 8117sci3.html,

http://www.prophezine.com/search/database/DailyNews/data/news/10I7272078.story.html

(Science and Technology Wed Mar 27 18:34:38 2002) water-soluble soap solution with the addition of special hardening polymers (the composition of the solution is classified, but it is available because it is widely sold around the world as toys for children). In air, they let it freeze for an hour in a strong polymer film with soap molecules on its surfaces. After drying, the stretched soap film becomes very strong and lives for months with the interference pattern characteristic of soap films frozen on it. Radiation of a He-Ne laser (632.8 nm, 10 mW) focused by a spherical lens (F = 10 cm) is directed onto the film surface at a sliding angle of not more than 20 °. With this setting, filamentous, brightly luminous, fixed, centimeter light channels of polariton radiation with the properties described above appear directly in the film directly from the focal point. By moving the focal point, you can change the direction of the mustache beam emerging from the focal point in the film.

It should be noted that, despite the wide range of available lasers, soap and non-soap, aqueous and non-aqueous solutions for films and the simplicity of experiments, the existence of polaritons in molecular structural films is not described in the literature, and it does not follow from the known theories for polariton radiation in the considered previously / 1, 2 / solid media and is not an obvious consequence of the known properties of these films. Thus, a new method has been discovered for obtaining surface polaritons with an increased concentration of their energy (in mustache) and a multi-centimeter path length in thin molecular-structural films and threads, which are a new, previously unknown medium for generating surface electromagnetic waves. The observed concentration of polariton radiation in a thin, non-diverging mustache, traveling tens of centimeters across the films, is a new, previously unknown physical phenomenon that contributes to the expansion of the properties of surface polaritons and their practical application.

For clarity, we briefly list the most important properties of the polariton radiation obtained in films that distinguish it from the bulk.

1. Radiation propagates along smooth and curved surfaces of the films, practically not attenuating, over long distances (tens of centimeters).

2. The brightest radiation tracks are obtained in gray (pre-black) films with a thickness of about 0.06 μm, where the beam optics no longer work. In thick films of 5-10 microns, radiation is excited less efficiently.

3. Polariton radiation perceives films of different thicknesses as media with different refractive indices. For thin films, the refractive index is close to 1, for thick films it increases to 1.25-1.28. The corresponding speed of the excited light flux is less than the speed of light in air, but more than the speed of light in solution. From the contact boundaries of films of different thicknesses (or films with a bulk solution), radiation is partially reflected. There is a limiting angle (about 50-52 °) for the entrance of exciting radiation from the solution into the film.

4. It is most effectively excited by laser radiation with polarization perpendicular to the film through an edge or when illuminated from the side on film irregularities (dust particles). The excitation efficiency (brightness) sharply increases when it is directed along the film or laterally through the air to spontaneously appearing boundaries of films of different thicknesses (black and pre-black) with sliding angles of incidence of the pump (up to 20 °). In this case, the polarization of the laser beam can be parallel with the film. Focusing the pump flow above and below this boundary does not produce any whiskers in the film.

5. It does not occur in the volume of liquids and solutions and on the surfaces of liquids and soap solutions with surfactants under the same excitation conditions with the films.

6. It has the appearance of mobile, extremely thin (submicron), not diverging or branching whiskers with an unexpectedly high glow intensity. When crossing, the mustache does not have a visible effect on each other. When leaving the films, this radiation becomes divergent.

Possible applications

Surface polaritons can be used in various applied devices of optoelectronics, integrated optics and electronics / 1-5 /. Radiation traveling along the surface is useful for studying processes at the boundaries, surfaces of films, drainage and stratification of the solution in them, aging, changes in the composition, thickness of soap films in various devices / 7 /. As noted in clause 15, films with polariton radiation can be used as sensitive sensors, for example, to monitor for the presence of tiny droplets of fog in the air surrounding them. The compression and concentration of polariton radiation in the whiskers of films and filaments can be used to obtain cylindrical surface polaritons for near-field scanning optical microscopes and observation of submicron dust particles in the films themselves. The ability to control the magnitude of the refractive index by an external field (electric, magnetic, sound, thermal, etc.) opens up the prospects of simple film optoelectronic devices, switches, couplers, polarizers, etc., the possibility of implementing devices such as a laser “needle”, optical turbulence, studies of the connection of whiskers with cylindrical surface phonon-polariton waves on a monolayer crystal lattice of surfactant molecules, study of the interaction of polariton waves on two closely spaced parallel soap films, the effect of polaritons on phonon surface waves in the film. In addition, as we found, a high concentration of dye molecules in the same films in which the formation of polariton radiation is observed allows them to be simultaneously used as an active laser medium and, upon intense excitation (532 nm, 10 ns), they can receive tunable laser generation on molecules dyes (as in dye solution lasers) and study its interaction with surface polariton radiation.

In essence, in polariton physics it will find a new type of surface polariton radiation, for which the presented results prove three important previously unknown existence theorems:

1. There are media in which this polariton radiation exists only in thin (<10 μm) films and filaments, but does not exist on the surface of these bulk media.

2. There are environments in which polariton radiation of the visible range has a range of tens of centimeters.

3. There are environments in which polariton radiation is compressed, concentrated, and forms self-sustaining submicron thin filaments (whiskers).

The practical question is raised about expanding the class of such media and making their analogues on the basis of specially prepared chemically and physically strong submicron, for example, polymer films coated with monolayers of molecules with the required polarization properties.

Literature

1. Surface polaritons. Electromagnetic waves on surfaces and interfaces. / Ed. V.M. Agranovich, D.L. Mill. M: Science 1985.

2. NL.Dmitruk, V.G. Litovchenko, V.L. Strizhevsky. Surface polaritons in semiconductors and dielectrics. Kiev: Naukova Dumka, 1989.

3. J. C. Weber and A. Dereux Ch. Girard and G. Colas des Francs J. R. Krenn J. P. Goudonnet "Optical addressing at the subwavelength scale" PHYSICAL REVIEW E NOVEMBER 2000 VOLUME 62, NUMBER 5, p. 7381.

4. H. Ditlbacher, J. R. Krenn, a) G. Schider, A. Leitner and F. R. Aussenegg "Two-dimensional optics with surface plasmon polaritons" APPLIED PHYSICS LETTERS VOLUME 81, NUMBER 10, 2 SEPTEMBER, 2002, p. 1762.

5. J.-C. Weeeber, JRKrenn, A. Dereux, B. Lamprecht, Y. Lacroute, JP Goudonnet, "Near-field observation of surface plasmon polariton propagation on thin metal stripes" PHYSICAL REVIEW B, VOLUME 64, 045411 2001, p. 64 (http: //nanooptics.uni-graz. At / ol / papers / PRBO 1 weeber.pdf).

6. US Pat. # 6,442,321, Berini, August 27, 2002 "Optical waveguide structures".

7. A.B. Startsev, Yu.Yu. Stoilov Film ispalators. - Quantum Electronics, 32, No. 5 (2002), p. 463.

Claims (2)

1. A method of producing surface polaritons, characterized in that the exciting laser beam is directed at a sliding angle not exceeding 20 ° to the surface of a liquid or polymer film with a thickness of less than 10 μm, the surfaces of which are coated with a molecular layer of polar molecules, or introduced into the edge of the specified liquid or polymer film, or injected into the end of a liquid filament having a thickness of less than 10 μm and coated with a layer of polar molecules. 2. The method according to claim 1, characterized in that use a film or thread from an aqueous solution, coated with a layer of molecules of surface-active substances (surfactants).

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