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arXiv:2605.24483

Quantum Otto machine with $q$-deformed Pöschl-Teller oscillator

Collins O. Edet, Norshamsuri Ali, Rosdisham Endut, O. Abah

quant-phSubmitted May 23, 2026• Announced May 26, 2026• 0 citations
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Abstract

We study the impact of the potential parameters of the q-deformed modified Pöschl-Teller potential on the thermodynamic performance of a quantum Otto cycle, where the $q$-deformed modified Pöschl-Teller potential serves as the working substance. Analytical expressions for the energy spectrum and wave functions are derived, enabling a systematic investigation of heat exchange, work output, efficiency, and coefficient of performance. We show that $q$-deformation modifies the energy spectrum and creates distinct performance regions in the ($q$, $Δ$) parameter space. Low ($Δ$) and high ($q$) favour optimal heat engine efficiency, whereas high ($Δ$) and low ($q$) improve refrigerator performance. The heat engine efficiency peaks in the low-($Δ$), high-($q$) regime. These results highlight the q-deformed modified Pöschl-Teller potential as a versatile and tunable platform for exploring potential parameter-driven effects in quantum thermal machines.

Comments
10 pages, 5 figures

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ABSTRACT We study the impact of the potential parameters of the q‐deformed modified Pöschl–Teller potential on the thermodynamic performance of a quantum Otto cycle, where the ‐deformed modified Pöschl–Teller potential serves as the working substance. Analytical expressions for the energy spectrum and wave functions are derived, enabling a systematic investigation of heat exchange, work output, efficiency, and coefficient of performance. We show that ‐deformation modifies the energy spectrum and creates distinct performance regions in the (, ) parameter space. Low () and high () favor optimal heat engine efficiency, whereas high () and low () improve refrigerator performance. The heat engine efficiency peaks in the low‐(), high‐() regime. These results highlight the q‐deformed modified Pöschl–Teller potential as a versatile and tunable platform for exploring potential parameter‐driven effects in quantum thermal machines.
Abstract We present quantum heat machines using a diatomic molecule modeled by a q -deformed Morse potential as a working medium. We analyze the effect of the deformation parameter and other potential parameters on the work output and efficiency of the quantum Otto and quantum Carnot heat cycles. Furthermore, we derive the analytical expressions of work and efficiency as a function of these parameters. Interestingly, our system operates as a quantum heat engine across the range of parameters considered. In addition, the efficiency of the quantum Otto heat engine is seen to be tunable by the deformation parameter. Our findings provide useful insight for understanding the impact of anharmonicity on the design of quantum thermal machines.
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