Importance of space-charge effects in resonant tunneling devices

Abstract
The consideration of space charge in the analysis of resonant tunneling devices leads to a substantial modification of the current-voltage relationship. The region of negative differential resistance (NDR) is shifted to a higher voltage, and broadened along the voltage axis. Moreover, the peak value of current prior to NDR is reduced, leading to a reduction in the predicted peak-to-valley ratio. An approach is presented to include space-charge effects, and a recently fabricated GaAs-AlxGa1−xAs structure is analyzed, to underscore the importance of a self-consistent electrostatic potential in theoretical calculations.