Plasma Z-Pinch
Electric current creates magnetic field that compresses plasma inward
The Z-pinch: current flows along the Z-axis (vertical) through plasma. By Ampère's law, this creates a toroidal (circumferential) magnetic field Bθ ∝ I/r. The J×B (Lorentz) force points inward, compressing the plasma. Bennett's relation: the equilibrium radius balances magnetic pressure against plasma pressure 2nkT. Instabilities (sausage, kink) disrupt the pinch — fusion research moves toward tokamaks (adding axial B field for stability).