Legal Aspects

For the creation of powerful laser diodes and their basic matrixes, a modified method of Liquid Phases Epitaxy (LPE) will be used allowing for the formation of low threshold heterostructures with quantum size layers. In order to increase the optical capacity of laser diodes, the following are planned: research directed at searching for an optimum type of laser diode resonator, and the use of proton implantation in the formation of current channels, the lateral walls of the resonator and near mirror insulation areas (a number of technical aspects are patented in Russia).

Scientific Papers None.

Foreign Collaborators TRW Inc.

№ -0130 Plasma Accelerator Based Facilities for Plasma High Heat Flux Tests

Full Title:	Plasma Accelerator Based Facilities for Plasma High Heat Flux Tests of Energy Stressed Components of Energetic Equipment, and Materials and Plasma Physics Research
Technology Field(s):	FUS-PLA: Fusion / Plasma Physics FIR-MAT: Fission Reactors / Materials SAT-OTH: Space, Aircraft and Surface Transportation / Other

Contributors

Vladimir N Litunovsky

Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA Efremov) P.O. Box 42, St Petersburg, 189631, Russia Phone: 7+812+4627991; 7+812+2655991 Fax: 7+812+4644623; 7+812+4639812; 7+812+3143360 filatov@niiefa.spb.su

Present Status of Research

Brief Description of Research

The special research complex for experiments on the study of the interaction of intensive plasma streams with materials has been created at the Efremov Institute. In these facilities, the high power long-pulse coaxial plasma accelerators are used as sources of plasma high heat flux. The facilities are equipped with a sample holder, a lock chamber and a sample heater (T = RT-1000 °C). The combined calorimeter-ballistic pendulum system is located in the lower part of the interaction chamber to facilitate current check-up of integral parameters of the plasma stream. The power supply, 5 kV, 100 kJ artificial forming line, allows for the generation of a rectangular-like discharge current with variable duration in the load (plasma gun). The unique parameters of plasma streams allow for the performance of scientific research on a modern level and in a wide range of applications. The achieved values of the plasma stream allow for the simulation, for example, of plasma load on Plasma Facing Components of big Tokamaks and the future Fuel reactor during off-normal events, such as plasma disruptions and ELMs (main current activity in EI). Additionally, it is possible to use these facilities for other applications: plasma technology, plasma-material interaction (i.e. sattelite body damage during braking in the atmosphere, etc.), plasma-magnetic field interaction (formation of Plasma Compact Toroids), etc. The diagnostics complex (spectroscopy in visible and VUV regions of the spectrum, high speed photography, laser beam absorption, interpherometry) is also used for measuring plasma parameters of both the incident plasma stream and the plasma-material interaction zone. Such a compact, relatively cheap and simple facility can also be used for education processes in universities and laboratories.

Special Facilities

The experimental complex includes three facilities that are able to generate plasma streams with plasma parameters of a wide region. The main parameters are given in the following table:

Parameters VIKA SAPFIR SPRUT

Specific energy (kJ/cm²) 3 (up to 12) 0.2 0.5 Proton energy (eV) ~250 ~500 ~100 Pulse duration (ms) 0.1 to 0.36 0.2 0.3 to 1.0 Plasma dia. (cm) ~3 ~10 ~35 Magnetic field (T) 5 to 2 5 to 2 5 to 2

Scientific Papers

V.R.Barabach, A.G.Baranov, T.A.Burtseva, V.L.Komarov, V.N.Litunovsky, I.B.Ovchinnikov, G.L.Saksagansky and V.Fabritsiev, “Damage of refractory metals and carbon-based materials under simulation of the thermal influence of plasma disruptions,” Fusion Eng. and Design, 18, pp. 145-150 (1991).

V.R.Barabach, A.G.Baranov, V.N.Litunovsky, I.B.Ovchinnikov, J.Gahl, J.McDonald, “Experimental study of pulse plasma-carbon materials interaction during the simulation of thermal quench phase of tokamak plasma disruption”, J. of Nucl. Materials, 187, pp. 298-302 (1992).

V.M.Kozhevin, V.E.Kuznetsov, V.N.Litunovsky, I.B.Ovchinnikov, V.A.Titov et al., “Experimental simulation of plasma heat flux-material interaction during ITER plasma disruption,” Fusion Eng. and Design, 28, pp. 157-161 (1995).

P.D.Rockett, J.A.Hunter, J.T.Bradley, J.M.Gahl, V.N.Litunovsky, I.B.Ovchinnikov, V.E.Kuznetsov, V.A.Titov et al., “Studies of ablated plasma from experimental plasma gun disruption simulation,” J. of Nucl. Materials, 220-222, pp. 785-787 (1995).

V.A.Gagen-Torn, I.R.Kirillov, V.L.Komarov, V.N.Litunovsky, I.B.Obchinnikov et al., “Experimental complex for high heat flux-material interaction research,” Fusion Technology, Proc. of 18th SOFT, Karlsruhe, v.I, pp. 363-366 (1994).

V.N. Litunovskly, I.B. Ovchinnikov, A.A. Drozdov et al., “Study of material response on simulated ITER disruptive plasma heat load with variable duration,” IEEE/NPSS 16th Symposium Fusion Engineering, eds. G.H.Miley and C.M. Elliott, IEEE, Piscataway, NJ, Vol. 1, pp. 435-438 (1996).

V.A.Burtsev, V.M.Kozhevin, V.N.Litunovsky et al., “The Pulsator Concept as a Possible Technique for Formation of a Field Reversed Configurations, Fusion Technology”, v.21, No.4, pp. 2332-2345 (1992).