Normal and anomalous electron-hole pairs in a quantum conductor driven by a voltage pulse

摘要

Electron-hole pairs can be excited coherently in a quantum conductor by applying voltage pulses to its contact. We find that these electron-hole pairs can be classified into two kinds, whose excitation probabilities have different dependences on the Faraday flux of the pulse. Most of the pairs are of the first kind, which can be referred to as "normal" pairs. Their excitation probabilities increase nearly monotonically with the flux and saturate to the maximum value of 1 when the flux is large enough. In contrast, there exist "anomalous" pairs, whose excitation probabilities can exhibit oscillations with the flux. These pairs can be excited by only pulses with a small width. Due to the oscillation of the probabilities, the anomalous pairs can lead to different features in the full counting statistics of the electron-hole pairs for pulses with integer and noninteger fluxes.