Cross-Field-Current Driven Lower-Hybrid Instability and Stochastic Ion Heating

A suprathermal electron beam is injected parallel to $\overrightarrow{\mathrm{B}}$ in a low-$\beta$ plasma. The sharp space-potential drop across the surface of the beam generates a strong cross-field current which in turn drives a modified two-stream instability at the lower hybrid frequency. Intense stochastic ion heating is observed with the onset of the instability, and the heating rate is found to be proportional to the wave energy.