## Abstract

Recent theoretical calculations, demonstrating that quantized charge transfer due to adia- batically modulated potentials in mesoscopic devices can result purely from the interference of the electron wave functions (without invoking electron-electron interactions) are reviewed: (1) Anew formula is derived for the pumped charge Q (per period); It reproduces the Brouwer formula without a bias, and also yields the effect of the modulating potential on the Landauer formula in the presence of a bias. (2) For a turnstile geometry, with time-dependent gate voltages V_{L}(t) and the magnitude and sign of Q are determined by the relative position and orientation of the closed contour traversed by the system in the {V_{L} - V_{R}} plane, relative to the transmission resonances in that plane. Integer values of Q (in units of e) are achieved when a transmission peak falls inside the contour, and are given by the winding number of the contour. (3) When the modulating potential is due to surface acoustic waves, Q exhibits a staircase structure, with integer values, reminiscent of experimental observations.

Original language | English |
---|---|

Pages (from-to) | 77-82 |

Number of pages | 6 |

Journal | Journal of the Physical Society of Japan |

Volume | 72 |

Issue number | SUPPL. A |

DOIs | |

State | Published - 1 Jan 2003 |

Externally published | Yes |

## Keywords

- Interference in nanostructures
- Quantum pumping
- Resonant transmission
- Surface acoustic waves