Maximizing free energy gain

Abstract

Maximizing the amount of work harvested from an environment is important for a wide variety of biological and technological processes, from energy-harvesting processes such as photosynthesisto energy storage systems such as fuels and batteries. Here we consider the maximization of free energy -- and by extension, the maximum extractable work -- that can be gained by a classical or quantum system that undergoes driving by its environment. We consider how the free energy gain depends on the initial state of the system, while also accounting for the cost of preparing the system. We provide simple necessary and sufficient conditions for increasing the gain of free energy by varying the initial state. We also derive simple formulae that relate the free energy gained using the optimal initial state rather than another suboptimal initial state. Finally, we demonstrate that the problem of finding the optimal initial state may have two distinct regimes, one easy and one difficult, depending on the temperatures used for preparation and work extraction. We illustrate our results on a simple model of an information engine.

23 pages

References in corpus (25)

• Stochastic thermodynamics, fluctuation theorems, and molecular machines
• Fundamental limitations for quantum and nano thermodynamics
• The Resource Theory of Quantum States Out of Thermal Equilibrium
• Maximal work extraction from quantum systems
• Work extraction and thermodynamics for individual quantum systems
• Optimal finite-time processes in stochastic thermodynamics
• Second law and Landauer principle far from equilibrium
• Work and information processing in a solvable model of Maxwell's demon
• Information-theoretic approach to the study of control systems
• Thermodynamics of quantum systems with multiple conserved quantities
• An autonomous and reversible Maxwell's demon
• Correlating thermal machines and the second law at the nanoscale
• Monotonicity of the Quantum Relative Entropy Under Positive Maps
• Geometrical aspects of entropy production in stochastic thermodynamics based on Wasserstein distance
• Continuity bounds on the quantum relative entropy
• A Resource Theory for Work and Heat
• Quantum thermodynamics of correlated-catalytic state conversion at small-scale
• Phase transition in protocols minimizing work fluctuations
• Is stochastic thermodynamics the key to understanding the energy costs of computation?
• Dependence of dissipation on the initial distribution over states
• Initial-State Dependence of Thermodynamic Dissipation for any Quantum Process
• From single-shot to general work extraction with bounded fluctuations in work
• Thermodynamics of computations with absolute irreversibility, unidirectional transitions, and stochastic computation times
• Dependence of integrated, instantaneous, and fluctuating entropy production on the initial state in quantum and classical processes
• Universal bounds on optimization of free energy harvesting