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Evolution of a Non-Hermitian Quantum Single-Molecule Junction at Constant Temperature
Andrea Grimaldi1, Alessandro Sergi1,2,3, Antonino Messina4
1Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università degli Studi di Messina, 98166 Messina, Italy.
Entropy (Basel, Switzerland)
|January 28, 2021
Summary
Thermal fluctuations and probability losses enhance quantum transport in molecular junctions. This study introduces a theory for non-Hermitian quantum systems, aiding molecular junction dynamics research.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Theoretical chemistry
Background:
- Understanding quantum dynamics in molecular junctions is crucial for nanoelectronics.
- Non-Hermitian quantum systems and thermal effects present significant theoretical challenges.
Purpose of the Study:
- To develop a theoretical framework for non-Hermitian quantum systems in thermal environments.
- To model and investigate quantum transport in a non-Hermitian quantum single-molecule junction (nHQSMJ).
Main Methods:
- Operator-valued Wigner formulation of quantum mechanics.
- Derivation of a non-linear equation of motion for non-Hermitian systems.
- Modeling nHQSMJ with a two-level system coupled to a harmonic mode and a Nosé-Hoover thermostat.
Main Results:
- The developed theory successfully describes quantum dynamics in non-Hermitian systems.
- Numerical simulations reveal that probability losses and thermal fluctuations collectively facilitate quantum transport.
- The model demonstrates the influence of temperature on quantum transport dynamics.
Conclusions:
- The proposed theory provides a robust method for studying complex quantum systems.
- Combined thermal fluctuations and probability losses can be beneficial for quantum transport.
- The formalism is extensible to larger and more complex quantum and classical systems.
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