Driving Quantum Heat Engines Beyond Classical Limits through Multilevel Coherence

• URL: http://arxiv.org/abs/2604.04873v1
• Date: Mon, 06 Apr 2026 17:24:03 GMT
• Title: Driving Quantum Heat Engines Beyond Classical Limits through Multilevel Coherence
• Abstract summary: We show the enhanced temperature tunability achievable via $N$-level ground-state coherence.<n>We also unify ground- and excited-state coherence within a single analytic framework.<n>We identify rubidium atoms as a promising candidate for experimentally realizing these coherence-assisted effects.
• Score: 1.4331799286130626
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Quantum coherence provides a controllable thermodynamic resource that can raise or lower the effective temperature of a cavity mode, enabling efficiency tuning in quantum heat engines. Here, we derive analytic expressions for the effective engine temperature, demonstrating the enhanced temperature tunability achievable via $N$-level ground-state coherence. We further unify ground- and excited-state coherence within a single analytic framework, revealing their interplay as a mechanism for thermodynamic control. Such quantum resources serve as tunable parameters that enable switching between heating, cooling, and cancellation regimes, driving the effective temperature from near-zero to divergence. Ultimately, our framework connects and generalizes previous models of quantum heat engines, and we identify rubidium atoms as a promising candidate for experimentally realizing these coherence-assisted effects.

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