Sub-1K Cold-Electron Quantum Well Switching at Room Temperature.

Quantum states can provide means to systematically manipulate the transport of electrons. Here we present electron transport across quasi-bound states of two heterogeneous quantum wells (QWs), where the transport of thermally excited electrons is blocked or enabled depending on the relative positions of the two quasi-bound states, with an abrupt current onset occurring when the two QW states align. The QW switch comprises a source (Cr), QW1 (CrO), QW2 (SnO, < 2), a tunneling barrier (SiO), and a drain (Si), where the effective electron mass of QW1 (*) is selected to be larger than QW2 (*).