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Updated: Jun 3, 2026
10:26
Fabrication and Characterization of Superconducting Resonators
Published on: May 21, 2016
Exact results for nonlinear ac transport through a resonant level model
1Physics Department, Arnold Sommerfeld Center for Theoretical Physics, and Center for NanoScience, Ludwig-Maximilians-Universität, Theresienstrasse 37, D-80333 Munich, Germany. pei.wang@physik.lmu.de
Summary
We present exact results for electron transport through a resonant level model, analyzing transient and steady-state behaviors under voltage bias. The study reveals phenomena like current ringing and photon-assisted tunneling (PAT) oscillations.
Area of Science:
- Condensed matter physics
- Quantum transport phenomena
Background:
- The Anderson impurity model describes electron interactions with a localized magnetic impurity.
- Understanding quantum transport is crucial for developing novel electronic devices.
Purpose of the Study:
- To derive exact analytical results for time-dependent transport through a resonant level.
- To investigate both transient and steady-state current responses to a rectangular voltage bias.
- To explore phenomena beyond linear response, including large voltage bias effects.
Main Methods:
- Exact solution of the resonant level model (noninteracting Anderson impurity model).
- Analysis of time evolution after applying a voltage bias at t=0.
- Derivation of explicit expressions for AC current in linear and nonlinear regimes.
Main Results:
- Obtained exact time-dependent current for a rectangular voltage bias.
- Observed transient current ringing phenomenon.
- Identified photon-assisted tunneling (PAT) oscillations beyond linear response.
- Characterized steady-state current behavior.
Conclusions:
- The resonant level model exhibits rich dynamical behavior under time-varying voltage bias.
- Current ringing and PAT oscillations are key signatures of quantum transport in this system.
- Analytical results provide a benchmark for numerical simulations and experimental interpretations.
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