A plasma pinch having an inner/outer coaxial tube arrangement, which nested tube arrangement yields a higher-performance pinchlamp than is capable with a single-tube configuration. Further, each tube contains a separate gas, the inner tube filled with Argon, and the outer tube filled with Helium. The inner/outer coaxial tube arrangement of the present invention facilitates the use of an inner tube to contain a volume of Argon gas as the working gas. The outer tube is coaxial with the inner tube, surrounding the inner tube with contained Helium gas. The configuration of an outer tube filled with Helium presents external pressures to the inner tube. The contained Helium gas in the outer tube, among other things, compresses and supports the walls of the inner tube, enabling the inner tube to be smaller in diameter than prior art plasma chambers, which chambers would shatter if made with as small a diameter as the present inner tube.