Electrical control of tunnel characteristics is demonstrated in a vertically coupled quantum point contact (VCQPC) formed in a bilayer two-dimensional electron system. In this VCQPC, the geometry of potential is controlled by voltages applied to split-gates, a midline-gate, and a back-gate. In particular, the vertical alignment of upper and lower quantum point contact (QPCs) can be electrically tuned. When the two QPCs are misaligned, coupling appears between all one-dimensional (1D) subbands arising from the two QPCs. The coupling strength between the lowest 1D subbands becomes smaller with increasing misalignment because of the smaller overlap of the wavefunctions.
|Journal||Applied Physics Letters|
|Publication status||Published - 2013 Aug 5|
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)