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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Dynamics and thermodynamics of linear quantum open systems.
Esteban A Martinez1, Juan Pablo Paz
1Departamento de Física, FCEyN, UBA, Ciudad Universitaria Pabellón 1, 1428 Buenos Aires, Argentina.
Physical Review Letters
|April 16, 2013
Summary
This study reveals that quantum networks coupled to environments follow a master equation, with nonlinearity essential for quantum absorption refrigerators. The third law of thermodynamics constrains environmental spectral densities.
Area of Science:
- Quantum mechanics
- Thermodynamics
- Quantum information theory
Background:
- Understanding the quantum state evolution of coupled systems is crucial for quantum technologies.
- Investigating the emergence of thermodynamic laws from quantum dynamics is a key theoretical challenge.
Purpose of the Study:
- To analyze the quantum state evolution of networks of quantum oscillators coupled to external environments.
- To explore the emergence of thermodynamic laws, specifically the third law, in the long-time regime.
- To determine the role of nonlinearity in quantum absorption refrigerators.
Main Methods:
- Derivation of a local master equation for the reduced density matrix of quantum networks.
- Analytical solution of the master equation for systems coupled to arbitrary environments.
- Investigation of long-time behavior to study emergent thermodynamic properties.
Main Results:
- The reduced density matrix of quantum networks obeys a local master equation with a simple analytical solution.
- Nonlinearity is demonstrated to be an essential resource for quantum absorption refrigerators.
- The third law of thermodynamics imposes constraints on the low-frequency behavior of environmental spectral densities.
Conclusions:
- Quantum networks coupled to environments are well-described by local master equations.
- Linear networks are insufficient for building quantum absorption refrigerators, highlighting the importance of nonlinearity.
- Environmental spectral densities play a critical role in upholding thermodynamic laws at the quantum level.
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