Optimal power and efficiency of single quantum dot heat engines: theory and experiment

Abstract

Quantum dots (QDs) can serve as near perfect energy filters and are therefore of significant interest for the study of thermoelectric energy conversion close to thermodynamic efficiency limits. Indeed, recent experiments in [Nat. Nano. 13, 920 (2018)] realized a QD heat engine with performance near these limits and in excellent agreement with theoretical predictions. However, these experiments also highlighted a need for more theory to help guide and understand the practical optimization of QD heat engines, in particular regarding the role of tunnel couplings on the performance at maximum power and efficiency for QDs that couple seemingly weakly to electronic reservoirs. Furthermore, these experiments also highlighted the critical role of the external load when optimizing the performance of a QD heat engine in practice. To provide further insight into the operation of these engines we use the Anderson impurity model together with a Master equation approach to perform power and efficiency calculations up to co-tunneling order. This is combined with additional thermoelectric experiments on a QD embedded in a nanowire where the power is measured using two methods. We use the measurements to present an experimental procedure for efficiently finding the external load $R_P$ which should be connected to the engine to optimize power output. Our theoretical estimates of $R_P$ show a good agreement with the experimental results, and we show that second order tunneling processes and non-linear effects have little impact close to maximum power, allowing us to derive a simple analytic expression for $R_P$. In contrast, we find that the electron contribution to the thermoelectric efficiency is significantly reduced by second order tunneling processes, even for rather weak tunnel couplings.

References in corpus (39)

• Mesoscopic quantum transport: Resonant tunneling in the presence of strong Coulomb interaction
• Reversible thermoelectric nanomaterials
• Thermoelectric energy harvesting with quantum dots
• Thermoelectric efficiency at maximum power in a quantum dot
• A quantum-dot heat engine operating close to the thermodynamic efficiency limits
• Most efficient quantum thermoelectric at finite power output
• Quantum limit of heat flow across a single electronic channel
• Giant thermopower and figure of merit in single-molecule devices
• Modulation of Thermoelectric Power of Individual Carbon Nanotubes
• Three-Terminal Energy Harvester with Coupled Quantum Dots
• Thermopower of a Kondo-correlated quantum dot
• Thermopower of Single-Molecule Devices
• Optimal thermoelectric figure of merit of a molecular junction
• Large enhancement of thermoelectric effects in a double quantum dot system due to interference and Coulomb correlation phenomena
• Thermoelectric efficiency at maximum power in low-dimensional systems
• Increasing thermoelectric performance using coherent transport
• Kinetic Equations for Transport Through Single-Molecule Transistors
• Giant Thermoelectric Effect from Transmission Supernodes
• Solving rate equations for electron tunneling via discrete quantum states
• Cotunneling thermopower of single electron transistors
• Dynamical energy transfer in ac driven quantum systems
• Cotunneling at resonance for the single-electron transistor
• Heat transport through atomic contacts
• Nonlinear thermovoltage and thermocurrent in quantum dots
• Density-operator approaches to transport through interacting quantum dots: Simplifications in fourth-order perturbation theory
• Experimental realization of a quantum dot energy harvester
• Heat Coulomb Blockade of One Ballistic Channel
• Sequential and co-tunneling behavior in the temperature-dependent thermopower of few-electron quantum dots
• Thermal Conductance of a Single-Electron Transistor
• Thermoelectric properties of an interacting quantum dot-based heat engine
• Thermoelectric conversion at 30K in InAs/InP nanowire quantum dots
• Lineshape of the thermopower of quantum dots
• Fermionic superoperators for zero-temperature non-linear transport: real-time perturbation theory and renormalization group for Anderson quantum dots
• Thermoelectric characterization of the Kondo resonance in nanowire quantum dots
• Time-dependent quantum transport: causal superfermions, exact fermion-parity protected decay mode, and Pauli exclusion principle for mixed quantum states
• Experiments on thermoelectric properties of quantum dots
• Efficiency and power of a thermoelectric quantum dot device
• Non-Linear Thermovoltage in a Single-Electron Transistor
• Spin switching via quantum dot spin valves

Cited by in corpus (19)

• Heat driven transport in serial double quantum dot devices
• Efficient and tunable Aharonov-Bohm quantum heat engine
• Comparative study of heat-driven and power-driven refrigerators with Coulomb-coupled quantum dots
• Multitask quantum thermal machines and cooperative effects
• Stochastic Thermodynamic Cycles of a Mesoscopic Thermoelectric Engine
• Numerically "exact" simulations of a quantum Carnot cycle: Analysis using thermodynamic work diagrams
• Dynamics of a strongly coupled quantum heat engine -- computing bath observables from the hierarchy of pure states
• The laws of thermodynamics for quantum dissipative systems: A quasi-equilibrium Helmholtz energy approach
• Study of the energy variation in many-body open quantum systems: role of interactions in the weak and strong coupling regimes
• Thermoelectricity of near-resonant tunnel junctions and their near-Carnot efficiency
• Maximum Power of Coupled-Qubit Otto Engines
• Real-time observation of charge-spin cooperative dynamics driven by a nonequilibrium phonon environment
• The optimum configuration design of a nanostructured thermoelectric device with resonance tunneling
• A Strongly Correlated Quantum-Dot Heat Engine with Optimal Performance: An Non-equilibrium Green's function Approach
• Thermoelectric study of the time-dependent Resonant Level Model
• Current noise in quantum dot thermoelectric engines
• Accurately heat flow distribution based on a triple quantum dot
• Heat operator approach to quantum stochastic thermodynamics in the strong-coupling regime
• The reverse flow and amplification of heat in a quantum-dot system