Eugene M. Kudriavtsev

Soliton-type waves of reflection and conduction in metals at static loading as a possible tool of precatastrophic damage indications

Waves of change of reflection and conduction (WCRC) were suggested at Boulder-1997 as a new phenomenon for precatastrophic indications of laser damage in IR transparent semiconductors. It turned out from results of K. B. Abramovas team (many publications since 1971) that the WCRC-components are exciting in different metals mechanically by flat shock or static load. The velocity measurements were obtained from photomultiplier evolution of visible emission (mechanoluminescence) of the samples. Rapid deformation (approximately 10-4 s) of Cu-sample by subsonic body excited 5-th WCRC component (U5 approximately 0.08 km/s). Slow (approximately 400 s) change of the load from 3 to 8 tons (when destruction happened) gave 65% increasing of 20-th WCRC-component (U20 approximately 0.33 cm/s) in the case of Cu-sample. It gives again the possibility to develop the technique for the remote nondestructive precatastrophic indications of damage, now in metals. The work was done with financial support by RFBR, project 00-02-17249-(a), and by KIE.

Resonant IR laser-induced diffusion of oxygen in silicon

B.H.Makeev**,I.F.Mogilnik*, V.N.Pavlovich*, B.N.Romanuk***, V.I.Soroka*, V.V.Tokarevski*, S.D. Zotov***4nstitute for Nuclear Research, Kiev, USSR; **.Lebedev Physical Institute, 53 Leninsky pr.,117924 MoscowUSSR; ***Jnstjtute of Semiconductors, Kiev, USSRABSTRACTThe analysis of experimental data on resonant IR laser-induced diffusion of oxygen in silicon are presented in thiswork.Resonant irradiation leads to the increase of oxygen diffusion coefficient which corresponds to increase of effectivetemperature of the crystal approximately by three times. The control experiments included changing of laser emission

Sound velocity vl and vl/4 solitonlike wave components observation in ZnS excited by high-power IR laser pulse

Wave of Change of Reflection and Conduction (WCRC) is the new reversible IR laser induced phenomenon, which can present solitonic mechanism of heat transfer in solids. WCRC appears in answer to one exciting pulse as the consequence of the following each another pulses (wave-components) and could be important in many laser-surface interactions. One of the most interesting features of WCRC is the observed discrete (in 2 times) change of the velocity of each following component. Present work gives one more experimental proof of this statement.

Experimental study of visible reflection variation from high-temperature superconductor ceramics as a result of irradiation by excimer lasers

The present study started on the basis of a suggestion concerning possible structural modification of HT SC by means of laser irradiation with a frequency close to or in resonance with vibrational or electronic bonds of lattice. The research started in P. N. Lebedev Physical Institute in the frame of the program of IR-laser irradiation of HT SC using an unic 16 - 18 micrometers ED GDL CO2 laser, developed in this institute. An investigation of UV wavelengths effect on these ceramics was fulfilled with use of the high power excimer lasers facility of Marseille IMFM New Lasers Group. We report here on preliminary experiments related to reflectivity change of polarized He-Ne laser beam at Brewster angle in the cases of super conducting and non-super conducting ceramic oxides following excitation by ArF (193 nm) and XeCl (308 nm) excimer lasers for conditions below the ablation threshold.

Soliton-like excitations with discrete velocities in condensed matter: 10 years of investigations

The most important and experimentally established results of unusual solitary waves (pulses) are summarized, which taking place specifically in processes of laser-matter interactions and could be important also for active condense matter media of laser systems itself. This work was sponsored as project 00-02-17249 by RFBR (Russia).

Slow discrete velocity components of solitonic wave of change in reflection and conduction excited by CO2 laser pulse in Plexiglas and copper foil: experiments with thermocouple as detector

The experimental researches on excitation in Plexiglas of slow components of a solitonic-type Wave of change of reflection and conductivity (WCRC) are continued. Such discrete velocity excitations by a pulse of the CO2 laser (as first for ceramic HT SC samples) were found out by us in 1992. The results of soliton study in experiments with the various real condensed materials represent fundamental interest. We undertook the experiments with the use of the thermocouple as the detector with the purpose of increase of reliability of results received earlier by other methods, especially in relation to the sign of parameter variation in WCRC. Thus the assumption proves to be true stated by us before, that the arrival of a studied in Plexiglas results in local decreasing of temperature. The records of thermal processes in a copper foil sample for times in hundreds seconds after a stimulating pulse have allowed to register repeated passage through the foil several WCRC components with velocity of the order of μ/s. It is 104 times slower speed than in the first experiments of 1992.

Soliton-type waves of reflection and conduction in laser-matter interaction: as appeared in collected papers of the Symposium on Laser-Induced Damage in Optical Materials 1969-1998 (review)

Waves of change in reflection and conduction (WCRC)was found in 1992. Since that time, this multidimensional wave structure of solitonic types manifests itself in many works of different laboratories. It could be excited by electromagnetic, corpuscular radiation or by mechanical load at some conditions in different condense matter. Between many WRC features one of the most fundamental is 2-times decreasing of the velocity Ui of two following each another pulses, starting from longitudinal sound velocity vl(km/s), namely, Uiequalsvl/(2)i. The last pulse with iequals30 (seen in Cu massive sample) had velocity - micron/s. As a result of nearly constant Ui value and small losses at reflection these pulses exist in the sample for a long time. Here we reviewed hopefully all information about this phenomenon, which could be seen from original records of Boulder Symposiums publications in 1969-1998. This work was sponsored as project 00-02-17249 by RFBR (Russia).

Experimental data about the sign of local parameter variations in the solitary wave of change of reflection and conduction (WCRC) traveling through different condensed matter

Unusual solitonic-type excitations were found by our group in 1992. As it was shown since that time this waves travel trough different condensed matter with discrete velocities in the range of 9 orders of value (between km/s and less then μs). These waves can carry heat or cold as it can be seen from the sign of local parameters variation. Explanation to this facts one can find in suggestion that this waves could be as compression as expansion ones (the physical mechanism of all phenomenon not known yet). This work contains short review of experimental results, which show characteristically sign variation for different materials. This work was sponsored as projects 00-02-17249-(a) and 02-02-26611-(3) by RFBR, its presentation - by SPIE and KIE.

Excitation of the soliton-type wave of change of reflection and conduction in the rubber: new experimental data important for its mechanism development

It was shown experimentally, that in elastic soft polymer samples such as rubber the IR-laser pulse excites components of the soliton-like Wave of change of reflection and conduction (WCRC). It is most probable, that the arrival of a wave results in local decreasing of the temperature of different rubber samples. At room temperature the WCRC velocity measurement for two vacuum rubber samples with different thickness given agreeable data correspond to the nineteenth WCRC component. In crude, not polymerized rubber and at cooling of vacuum rubber up to approximately 230 K the WCRC also was excited. As well as in researches with plexiglas, in the present work of the effect of saturation of a new sample by components of soliton-like WCRC was observed. The obtained data confirm availability of soliton properties for studied WCRC and in applicability of the dislocations recombination mechanism as the causes resulting in formation WCRC. These results are important for the WCRC mechanism development. It presents a phenomenon, which in process of its research appears to be more and more universal. The work was made at financial support by RFBR, project 00-02-17249-(a), and by KIE.

Slow components of solitonic wave of change in reflection and conduction excited by CO2 laser pulse in plexiglass: experiments with IR detector

Experimental results of investigation in plexiglas support previously published our groups data of JR laser and e-beam excitation in solids of solitonic Wave of Change in Reflection and Conduction (WCRC). Method of single IR detector WCRC registration was applied in addition to JR thermovision method used before (there were used also -5other different methods). Results of slow WCRC components investigations showed that solitonic heat transfer play additional role to usual diffusive heat transfer. This role could be important at some conditions. As the control, the measured in this work WCRC component velocity ~ 0.26 cm/s does not depend from sample thickness which was equal 1.5 and 2.0 mm. Analysis of records treatment by help of (x-t) diagram permit to show many features of studied solitonic excitations lived in the solid sample during many minutes. Irradiation of the front surface by single laser pulse produced WCRC components; in experimental conditions of this work one can see pair components of the same velocity which were born as on front as on rear sample surface. They moved in different directions and reflects from sample surfaces many times with small energy losses. This work was sponsored by RFBR (Russia), project 97-02-17954-a) and 00-02-17249 a).