1210.7541 (Mihajlo Vanevic et al.)

Control of electron-hole pair generation by biharmonic voltage drive of
a quantum point contact    [PDF]

Mihajlo Vanevic, Wolfgang Belzig

The elementary excitations in a quantum contact with time-dependent voltage drive consist of single-electron excitations due to dc voltage offset and electron-hole pairs created by the ac voltage component. We show that the elementary excitations can be generated in a controlled way using harmonic and biharmonic time-dependent voltages applied to the contact and obtain the probabilities of the electron-hole pair creations. For a biharmonic voltage drive, we find that the probability of pair creation decreases in the presence of an in-phase second harmonic. This accounts for the suppression of the excess noise observed experimentally [Gabelli and Reulet, arXiv:1205.3638] proving that dynamic control and detection of elementary excitations in quantum conductors are within the reach of the present technology.

View original: http://arxiv.org/abs/1210.7541