CHARGE ACCUMULATION OVER A REGION OF ELECTRICAL MULTISTABILITY IN A DOUBLE-BARRIER STRUCTURE

When a double barrier semiconductor structure is biased near a tunneli ng resonance, charge can accumulate in the central quantum well. We re port photoluminescence measurements of the 2D charge density over the full range of a tunneling resonance with emphasis on the region of mul tistability, An active load line technique was used to bias the device into this region, which is otherwise inaccessible. The charge density versus current graph shows hysteresis and the plasmon excitation, whi ch is a strong feature in the current-voltage characteristic, appears only weakly. Both these results are consistent with a model calculatio n based on charge conservation and the electron-electron interaction.