Towards real-time testing of clocked Quantum Dot Cellular Automata

We present a real-time measurement of electron switching in clocked Quantum-Dot Cellular Automata (QCA) circuit, a QCA latch. A capacitively coupled radio frequency single electron transistor (RF-SET) with carrier frequency at 991.2 MHz is used as read-out electrometer. Reflection-mode detection of the SET impedance provides a fast response to changes of charge configuration in the latch dots. We demonstrate a QCA latch with operating temperature above 300 milli-Kelvin and clocking speed of 5 musec.