Emission rate of electron transport through a quantum point contact

Abstract

Electron emissions in mesoscopic conductors are inherently correlated due to the Pauli exclusion principle. In this paper, we show that the correlation can be read from the electron emission rate. To demonstrate this, we concentrate on the electron emission in a single-channel quantum point contact (QPC). The emission can be driven by either a dc bias voltage or an unit-charged Lorentzian voltage pulse. In the case of dc bias voltage, the correlation is pronounced at both short and long times. The long-time correlation can be effectively suppressed by increasing the electron temperature and/or decreasing the transmission probability of the QPC. In contrast, the short-time correlation is much robust. As a consequence, the emission at high temperatures and/or low transmission probabilities can be treated as a Poisson process at long times, but follows a non-Poisson renewal statistics at short times. In the case of Lorentzian pulse, the correlation is much sensitive to the electron temperature. As the electron temperature increases, the electron emission evolves gradually from a non-renewal process at low temperatures to a time-dependent Poisson process at high temperatures.