Abstract
Resonant tunneling through one-, two-, and three-dimensionally confined quantum wells from a three-dimensional electron source (emitter) is investigated theoretically. The three cases correspond to (1) the usual double-barrier structure, (2) a quantum-well ‘‘wire,’’ and (3) a quantum-well ‘‘box’’ or ‘‘dot.’’ Resonant tunneling currents exhibit different features for the three structures which can be easily understood in terms of the energy and momentum conservation involved in each case. A transfer Hamiltonian approach is used to predict current-voltage characteristics for square and round quantum wires and dots.