Voltage-Current Characteristics of Low Pressure Plasma Discharges

Credit: J. R. Roth (1995): Industrial Plasma Engineering: Volume I - Principles. Institute of Physics Press, Bristol, UK ISBN 0-7503-0318-2, Section 12.5.2, Section 9.6.3.

A voltage versus current plot of all low-density plasma discharge regimes (dark discharge, glow discharge and arc discharge modes). Resistance R (in ohms) is the ratio of voltage V (in volts) to current I (in amperes). R= (V / I). Except at the origin where no current flows, the graph never touches or crosses the lower axis. Thus V never reaches zero, thus (V / I) never reaches zero, thus resistance is non-zero for any current flowing through a low-density plasma. Low-density plasma is not a superconductor.

See:
Glow Discharges in low-pressure gases.
PSPICE SIMULATION OF ONE ATMOSPHERE UNIFORM GLOW DISCHARGE PLASMA (OAUGDP) REACTOR SYSTEMS