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Updated: May 24, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Nonequilibrium density-matrix description of steady-state quantum transport
Abhishek Dhar1, Keiji Saito, Peter Hänggi
1Raman Research Institute, Bangalore 560080, India.
Summary
This study presents an analytical method to determine the quantum transport density matrix for systems connected to reservoirs. It details calculations for electronic and phonon transport under steady-state nonequilibrium conditions.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Statistical mechanics
Background:
- Understanding quantum systems in nonequilibrium steady states is crucial for nanoscale devices.
- Current carrying states require detailed description of system-reservoir interactions.
- Reduced density matrix formalism is key to analyzing open quantum systems.
Purpose of the Study:
- To develop an analytical procedure for the stationary nonequilibrium density matrix.
- To investigate quantum transport in systems coupled to external reservoirs.
- To elucidate electronic and phonon transport phenomena.
Main Methods:
- Analytical derivation of the reduced density matrix.
- Utilizing quadratic Hamiltonians for system, reservoirs, and interactions.
- Applying tight-binding and harmonic models for electronic and phonon transport, respectively.
- Analyzing weak system-reservoir coupling limits.
Main Results:
- Explicit results for the reduced density matrix of current-carrying nonequilibrium steady states.
- Detailed procedure applicable to both electronic and phonon transport.
- Specific insights into interelectrode electron transport and low-dimensional phonon heat flux.
Conclusions:
- The developed analytical method provides a comprehensive framework for studying quantum transport.
- The findings are applicable to various transport setups in condensed matter systems.
- This work advances the understanding of nonequilibrium quantum phenomena.
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