Resonant Tunneling Characteristics in Symmetrical Triple-Barrier Structures with Outer Well

We propose "novel symmetrical triple-barrier structures with outer wells" and analyze theoretically tunneling characteristics for this structure. First, analytical expressions of the transmission coefficient and the resonance condition have been derived. Next, we have examined numerically tunneling time which is related to device operation speed. It is found that outer well can control tunneling time and that the proposed structures would be useful for designing high speed tunneling device