Efficiency of Harmonic Quantum Otto Engines at Maximal Power

Area of Science:

• Thermodynamics
• Quantum Mechanics
• Nanotechnology

Background:

• Recent advancements have led to the creation of the first nano heat engines, capable of utilizing quantum resources.
• A key question is how the efficiency of these quantum engines compares to classical engines, particularly at maximal power output.

Purpose of the Study:

• To analyze the efficiency of endoreversible Otto engines, both classical and quantum, within the Curzon-Ahlborn framework.
• To compare the efficiency at maximal power for quantum Otto cycles against classical counterparts and established efficiencies.

Main Methods:

• Analysis of two examples of endoreversible Otto engines.
• Application of the conceptual framework used by Curzon and Ahlborn for endoreversible Carnot cycles.
• Investigation of Otto cycles in both classical and quantum harmonic oscillators.

Main Results:

• For classical harmonic oscillators, the efficiency at maximal power in endoreversible Otto cycles matches the Curzon-Ahlborn efficiency.
• Quantum harmonic oscillators in Otto cycles exhibit significantly higher efficiency at maximal power compared to classical models.

Conclusions:

• The Curzon-Ahlborn efficiency is applicable to classical endoreversible Otto cycles at maximal power.
• Quantum effects in nano heat engines, specifically quantum harmonic oscillators, offer a pathway to efficiencies exceeding classical predictions.