Effect of magnetic field on the hysteresis phenomena and floating potential oscillations in a reflex plasma source

TL;DR

This study explores how magnetic fields influence hysteresis and oscillation behaviors in a reflex plasma source, revealing transitions from stable to chaotic oscillations as magnetic field strength varies.

Contribution

It provides new experimental insights into the magnetic field's role in modulating plasma oscillations and hysteresis phenomena in reflex plasma sources.

Findings

Magnetic field affects discharge current regimes and oscillation types.

Oscillation frequency increases with magnetic field strength.

Transition from periodic to chaotic oscillations occurs at higher magnetic fields.

Abstract

An experimental investigation on the periodic and chaotic oscillations in a reflex plasma source in presence of magnetic field is presented. The experiment is conducted in a reflex plasma source, consisting of two cathodes and a ring anode. A penning type DC glow discharge in an uniform axial magnetic field is initiated in the background of argon gas. The current-voltage characteristics near the breakdown voltage show a hysteresis with two distinct discharge current regimes. The effect of magnetic field on the discharge current and floating potential oscillations is studied when the discharge is operated within this hysteresis loop. At a typical axial magnetic field, the discharge transits from high discharge current regime (beyond 4-5 mA), an oscillation free regime, to a low discharge current regime (less than 1 mA). Depending upon the discharge parameters, low discharge current regime shows either the periodic or chaotic oscillation in the frequency range of 1-50 KHz. The frequency of periodic oscillation increases with the increase in magnetic field up to 90 Gauss and with further increase in magnetic field, the periodic oscillation becomes chaotic in nature.