ELECTRONIC DEVICE AND SINGLE ELECTRON ELEMENT HAVING COMPOUND TUNNEL BARRIER STRUCTURE

PURPOSE: To enable tunnel resistance change without changing the junction capacitance of a tunnel barrier, by constituting a compound tunnel barrier of a plurality of tunnel barriers different in barrier height. CONSTITUTION: A compound barrier structure is constituted of tunnel barriers having different barrier heights. When an electron tunnel from the diection A is considered, different tunnel resistances are shown in response to the different states of voltage. In this case, the junction capacitance does not change to electrons whichever path out of T1-Tn they may pass. When the electron tunnel is considered from the direction of B, the tunnel resistance shows a constant value independently of the state of voltage. By setting the tunnel resistance when electrons tunnel from the A direction smaller than the tunnel resistance when electrons tunnel from the B direction, directivity can be imparted to the tunnel resistance when electrons tunnel.