Study of Coulomb attractive random telegraph signal in surface acoustic wave based single electron transport (SAW/SET) devices

We investigated the random telegraph signal (RTS) in surface acoustic wave based single electron transport (SAW/SET) devices. In our experiment, the ratio of the average time at the high acoustoelectric (AE) current state to the average time at the low AE current state, τhigh/τlow, increases when the gate voltage is progressively positive, as well as the radio frequency (rf) power is increased and the offset voltage is gradually decreased. The experiment result indicates that the trap center is positively charged before trapping an electron. In this paper, we describe one kind of RTS attributed to the positively charged trap center. And we can get information on the spin properties of a single trap by investigating the magnetic field dependence of the average time ratio τhigh/τlow of the RTS.