Negative Differential Transconductance and Nonreciprocal Effects in a Y-Branch Nanojunction: High-Frequency Analysis

We report on negative differential transconductance (NDT) effect in Y-branch nanojunctions which leads to small-signal nonreciprocity of the device for certain biasing schemes. We present the dc analysis of the device from which we identify the bias regions where NDT effect occurs. We compare experimental dc measurements with results of Monte Carlo simulations, which yields very good qualitative and quantitative agreement. We perform a high-frequency analysis of the NDT effect up to 110 GHz which shows that the effect discussed is still present at such high frequencies