Curl flux, coherence, and population landscape of molecular systems: Nonequilibrium quantum steady state, energy (charge) transport, and thermodynamics

Abstract

We established a theoretical framework in terms of the curl flux, population landscape, and coherence for non-equilibrium quantum systems at steady state, through exploring the energy and charge transport in molecular processes. The curl quantum flux plays the key role in determining transport properties and the system reaches equilibrium when flux vanishes. The novel curl quantum flux reflects the degree of non-equilibriumness and the time-irreversibility. We found an analytical expression for the quantum flux and its relationship to the environmental pumping (non-equilibriumness quantified by the voltage away from the equilibrium) and the quantum tunneling. Furthermore, we investigated another quantum signature, the coherence, quantitatively measured by the non-zero off diagonal element of the density matrix. Besides the environment-assistance which can give dramatic enhancement of coherence and quantum flux with high voltage at a fixed tunneling strength, the quantum flux is promoted by the coherence in the regime of small tunneling while reduced by the coherence in the regime of large tunneling, due to the non-monotonic relationship between the coherence and tunneling. In view of the system as a quantum heat engine, we studied the non-equilibrium thermodynamics and established the analytical connections of curl quantum flux to the transport quantities such as energy (charge) transfer efficiency, chemical reaction efficiency, energy dissipation, heat and electric currents observed in the experiments. We observed a perfect transfer efficiency in chemical reactions at high voltage (chemical potential difference). Our theoretical predicted behavior of the electric current with respect to the voltage is in good agreements with the recent experiments on electron transfer in single molecules.

16 pages, 10 Figures

References in corpus (15)

• Experimental Observation of Quantum Hall Effect and Berry's Phase in Graphene
• Quantum Spin Hall Effect
• Quantum master equation for electron transport through quantum dots and single molecules
• Probability currents as principal characteristics in the statistical mechanics of non-equilibrium steady states
• Does coherence enhance transport in photosynthesis?
• Crossover from mesoscopic to universal phase for electron transmission in quantum dots
• Density functional calculations of nanoscale conductance
• Near-perfect conduction through a ferrocene-based molecular wire
• Efficient Energy Transfer in Light-Harvesting Systems, II: Quantum-Classical Comparison, Flux Network, and Robustness Analysis
• Transport in molecular states language: Generalized quantum master equation approach
• Quantum transport efficiency and Fourier's law
• Excitonic energy transfer in light-harvesting complexes in purple bacteria
• Potential and Flux Decomposition for Dynamical Systems and Non-Equilibrium Thermodynamics: Curvature, Gauge Field and Generalized Fluctuation-Dissipation Theorem
• Quantum effects in energy and charge transfer in an artificial photosynthetic complex
• Modelling light-driven proton pumps in artificial photosynthetic reaction centers

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• Coherence enhanced quantum metrology in a nonequilibrium optical molecule
• Nonlinear Spin Currents
• Origin of long-lived coherence and excitation dynamics in pigment-protein complexes
• Funneled Potential and Flux Landscapes Dictate the Stabilities of both the States and the Flow: Fission Yeast Cell Cycle
• Nonequilibrium Effects on Quantum Correlations: Discord, Mutual Information and Entanglement of a Two-Fermionic System in Bosonic and Fermionic Environments
• Steady bipartite coherence induced by non-equilibrium environment
• Shape, orientation and magnitude of the curl quantum flux, the coherence and the statistical correlations in energy transport at nonequilibrium steady state
• Nonequilibrium-induced enhancement of dynamical quantum coherence and entanglement of spin arrays
• Information Landscape and Flux, Mutual Information Rate Decomposition and Entropy Production
• Vibrational and coherence dynamics of molecules
• Universal Quantum Fluctuation-Dissipation Relation for Systems Far From Equilibrium
• Entanglement versus Bell nonlocality of quantum nonequilibrium steady states
• Thermodynamics of Reduced State of the Field
• Asymmetric steerability of quantum equilibrium and nonequilibrium steady states through entanglement detection
• Quantum Energy Teleportation under Equilibrium and Nonequilibrium Environments
• Quantum Teleportation in Non-equilibrium Environments and Fixed-point Fidelity
• Heat currents in qubit systems