Related Experiment Video
Updated: Jun 25, 2025
05:30
Large Scale Energy Efficient Sensor Network Routing Using a Quantum Processor Unit
Published on: September 8, 2023
538
Computational Issues of Quantum Heat Engines with Non-Harmonic Working Medium
Andrea R Insinga1, Bjarne Andresen2, Peter Salamon3
1Department of Energy Conversion and Storage, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
Entropy (Basel, Switzerland)
|May 24, 2024
Summary
We present a new method for analyzing quantum heat engines with non-harmonic oscillators. The harmonic oscillator basis offers the best computational performance for these complex quantum systems.
Area of Science:
- Quantum mechanics
- Thermodynamics
- Computational physics
Background:
- Quantum heat engines are crucial for understanding quantum thermodynamics.
- Analyzing non-harmonic oscillators presents significant computational challenges.
Purpose of the Study:
- To develop a computational framework for quantum heat engines with non-harmonic oscillators.
- To identify optimal numerical methods for simulating these systems.
Main Methods:
- Schrödinger picture for time evolution.
- Density operator expansion in various bases.
- Error estimation techniques for finite-dimensional approximations.
Main Results:
- The harmonic Hamiltonian eigenstate basis provides optimal computational performance.
- A method to quantify and reduce errors in extracting physical information was developed.
- The study addresses complexities of time-dependent Hamiltonians and thermal reservoirs in non-harmonic quantum heat cycles.
Conclusions:
- The harmonic basis is computationally superior for non-harmonic quantum heat engines.
- The developed techniques enable accurate numerical analysis of these complex systems.
- This work lays the foundation for future research in non-harmonic quantum heat machines.
Related Concept Videos
01:30The Carnot Cycle
2.9K
Converting work to heat is an irreversible process, and the purpose of a heat engine is to reverse the effect partially. Heat engines aim to increase the efficiency of the reversal, that is, maximize the work retrieved from heat. If the efficiency of a heat engine were 100%, it would imply reversing the process completely without introducing any other effect. Thus, it would violate the second law of thermodynamics.
What could be the theoretical limit to the efficiency of a heat engine? The...
What could be the theoretical limit to the efficiency of a heat engine? The...
2.9K
01:15Statements of the Second Law of Thermodynamics
4.0K
The second law of thermodynamics can be stated in several different ways, and all of them can be shown to imply the others. The Clausius’ statement of the second law of thermodynamics is based on the irreversibility of spontaneous heat flow. It states that heat will not flow from the colder body to the hotter body unless some other process is involved. Additionally, as per the Kelvin’s statement, it is impossible to convert the heat from a single source into work without any other...
4.0K
01:14Mechanisms of Heat Transfer
320
Heat transfer between the human body and its environment occurs through four main mechanisms: conduction, convection, radiation, and evaporation.
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant...
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant...
320
01:10Heat Engines
2.8K
A heat engine is a device used to extract heat from a source and then convert it into mechanical work used for various applications. For example, a steam engine on an old-style train can produce the work needed for driving the train.
Whenever we consider heat engines (and associated devices such as refrigerators and heat pumps), we do not use the standard sign convention for heat and work. For convenience, we assume that the symbols Qh, Qc, and W represent only the amounts of heat transferred...
Whenever we consider heat engines (and associated devices such as refrigerators and heat pumps), we do not use the standard sign convention for heat and work. For convenience, we assume that the symbols Qh, Qc, and W represent only the amounts of heat transferred...
2.8K
01:14Mechanisms of Heat Transfer I
4.2K
Just as interesting as the effects of heat transfer on a system are the methods by which the heat transfer occur. Whenever there is a temperature difference, heat transfer occurs. It may occur rapidly, such as through a cooking pan, or slowly, such as through the walls of a picnic ice box. So many processes involve heat transfer that it is hard to imagine a situation where no heat transfer occurs. Yet, every heat transfer takes place by only three methods: conduction, convection, and radiation.
4.2K
01:20Mechanisms of Heat Transfer II
3.2K
In convection, thermal energy is carried by the large-scale flow of matter. Ocean currents and large-scale atmospheric circulation, which result from the buoyancy of warm air and water, transfer hot air from the tropics toward the poles and cold air from the poles toward the tropics. The Earth’s rotation interacts with those flows, causing the observed eastward flow of air in the temperate zones. Convection dominates heat transfer by air, and the amount of available space for the airflow...
3.2K