INJECTED PLASMAS IN INDIUM ANTIMONIDE IN THE PRESENCE OF LONGITUDINAL MAGNETIC FIELDS

Technical Report · Fri Jun 01 04:00:00 EDT 1962

OSTI ID:4798348

Ancker-Johnson, B

The properties of injected electron-hole plasmas were investigated as a function of current I, electric field strength E, and longitudinal magnetic field strength B. A boundary in E-B space exists below which the plasma density remains essentially equal to the density obtained in the absence of an external magnetic field. In the regime B > B/sub critcial/ above the boundary the plasma is strongly dissipated. Oscillations occur in the subcritical regime only for high currents, I > I/sub pinch/. These pinch-unpinch'' oscillations have a nonreproducible waveform. Very reproducible oscillations were observed in the supercritical regime and their threshold frequencies were measured (a typical value is 25Mc). The data were compared to the predictions of the hydromagnetic screw instability theory. Agreement was found for the dependence of the critical electric field strengths and the threshold frequencies on the critical magnetic field strengths. Qualitative agreement required that the diameter of the injected plasma column be more than an order of magnitude smaller than the transverse dimensions of the sample. There were also some results which are inexplicable on the basis of the screw instability theory. Essentially infinite conductivity occurs in magnetic fields > B/sub crit/ at electric field strengths less than the impact ionization threshold. The plasma density is so greatly reduced by a longitudinal magnetic field that the reduction cannot be caused only by a perturbation, e.g., a reduction of 75% in 400G at 270v/cm. (auth)

• Research Organization: Boeing Scientific Research Labs., Seattle
• NSA Number: NSA-16-026400
• OSTI ID: 4798348
• Report Number(s): D1-82-0172
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ANTIMONY ALLOYS
CURRENTS
DENSITY
DISTURBANCES
ELECTRIC CONDUCTIVITY
ELECTRIC FIELDS
ELECTRONS
FREQUENCY
INDIUM ALLOYS
INJECTION
INTERACTIONS
INTERMETALLIC COMPOUNDS
IONIZATION
MAGNETIC FIELDS
MEASURED VALUES
OSCILLATIONS
PHYSICS
PINCH
PLASMA
STABILITY
SURFACES