发表机构
Zhejiang Normal University（浙江师范大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过量子缀饰主方程分析非对易耦合自旋系统的稳态热输运，发现弱耦合下存在负微分热导，强耦合下实现高效热整流，并扩展至三端结构构建量子热晶体管，实现热流放大。
AI 中文摘要
量子热输运支配着非平衡量子系统中的能量交换过程和统计规律，并在量子热力学中发挥着关键作用。我们研究了非对易耦合自旋系统的稳态热输运。我们采用开放量子系统理论框架下的量子缀饰主方程方法，以精确分析非平衡动力学，确保输运结果在强耦合区域的有效性。我们的结果表明，非对易自旋耦合是调节热流非线性的重要资源。具体而言，在弱自旋耦合区域，系统在不同自旋数下表现出稳健的负微分热导（NDTC）。通过推导单自旋和大自旋极限下热流的解析表达式，我们揭示了这种NDTC行为由微观循环流支配。物理上，这是因为在大的温度偏压下，冷库诱导的自旋激发通道被抑制，从而阻断了能量交换循环。相反，在强自旋耦合和大温度偏压区域，量子系统表现出显著的热整流效应。这种高整流效率源于热流的单向饱和，使该系统成为高性能热二极管的候选者。此外，我们将模型扩展到三端配置以构建量子热晶体管。通过操控栅极库的温度，我们实现了对源极和漏极之间热流的高效调制和放大。热放大因子在特定工作区域远大于1，证实了显著的热放大效应。
英文摘要
Quantum heat transport governs energy exchange processes and statistical laws in non-equilibrium quantum systems, and plays a pivotal role in quantum thermodynamics. We investigate the steady-state thermal transport of a noncommuting coupled spin system. We employ the quantum dressed master equation approach within the framework of open quantum system theory to accurately analyze the non-equilibrium dynamics, ensuring the validity of transport results in the strong coupling regime. Our results demonstrate that noncommuting spin coupling serves as a significant resource for modulating the nonlinearity of the heat current. Specifically, in the weak spin-coupling regime, the system exhibits robust negative differential thermal conductance (NDTC) across various spin numbers. By deriving analytical expressions for the heat current in both the single-spin and large-spin limits, we reveal that this NDTC behavior is governed by microscopic cycle fluxes. Physically, this arises because spin excitation channels induced by the cold reservoir are suppressed under a large temperature bias, thereby blocking energy exchange cycles. Conversely, in the strong spin-coupling and large temperature bias regime, the quantum system demonstrates pronounced thermal rectification. This high rectification efficiency originates from the unidirectional saturation of the heat current, rendering the system a promising candidate for high-performance thermal diodes. Furthermore, we extend the model to a three-terminal configuration to construct a quantum thermal transistor. By manipulating the temperature of the gate reservoir, we achieve efficient modulation and amplification of heat flow between the source and drain. The heat amplification factor is shown to far exceed unity in specific operating regions, confirming significant thermal amplification.
Comments6figs, 21pages
Journal refActa Phys. Sin., 2026, 75(9):090601
