Development of quantum functional devices for multiple-valued logic circuits

Quantum functional devices exhibiting unique current-voltage characteristics are reported for the application of multiple-valued logic circuits. Multiple negative-differential-resistance (NDR) characteristics in drain current-voltage characteristics are demonstrated by using multiple-junction surface tunnel transistors (MJ-STTs). Some multiple-valued logic gates such as inverter and literal are implemented using the MJ-STTs. Oscillatory characteristics of drain current under gate modulation are shown by single electron transistors. Nonvolatile multiple-valued memory devices utilizing these unique characteristics are described, and the fundamental operation of write and read of stored electrons are demonstrated.