Bhandari Tika Ram, Timsina Hari, Dhakal Chiranjibi, Adhikari Narayan Prasad
Central Department of Physics, Tribhuvan University, Kirtipur, Nepal.
Max Planck Institute of Polymer Research, Mainz, Germany.
Sci Rep. 2025 Jul 1;15(1):21119. doi: 10.1038/s41598-025-05018-9.
Transport phenomena are fundamental to understanding and optimizing quantum systems. This study investigates the transport properties of multidot quantum systems configured in series and parallel combinations, emphasizing two key aspects: the Wiedemann-Franz (WF) law and the Thermodynamic Uncertainty Relation (TUR). Using the scattering approach within the linear response framework, we analyze transmission functions, thermoelectric properties, and TUR. A general expression for quantum corrections under constant transmission conditions, where electron tunneling is probabilistic, is derived. Our findings reveal critical insights: (i) quantum phase transitions between weak and strong coupling regimes in parallel configurations, (ii) consistent violations of the WF law across all systems, and (iii) adherence to the TUR in the presence of the Aharonov-Bohm (AB) phase. Additionally, we report distinctive behaviors in transmission and thermoelectric properties, including charge and thermal conductance, the Lorenz ratio, and thermopower. For both constant and phase-dependent transmission scenarios, the TUR value consistently satisfies ≥ thresholds, and quantum corrections remain positive, underscoring their robustness. These results advance the understanding of quantum transport and provide a framework for optimizing performance in multidot quantum systems.
输运现象是理解和优化量子系统的基础。本研究调查了串联和并联配置的多量子点量子系统的输运性质，重点关注两个关键方面：维德曼-弗兰兹（WF）定律和热力学不确定性关系（TUR）。使用线性响应框架内的散射方法，我们分析了传输函数、热电性质和TUR。推导了在恒定传输条件下（电子隧穿是概率性的）量子修正的一般表达式。我们的研究结果揭示了关键见解：（i）并联配置中弱耦合和强耦合区域之间的量子相变，（ii）所有系统中对WF定律的一致违反，以及（iii）在存在阿哈罗诺夫-玻姆（AB）相位的情况下对TUR的遵守。此外，我们报告了传输和热电性质中的独特行为，包括电荷和热导率、洛伦兹比和热电势。对于恒定传输和与相位相关的传输情况，TUR值始终满足≥阈值，并且量子修正保持为正，突出了它们的稳健性。这些结果推进了对量子输运的理解，并为优化多量子点量子系统的性能提供了一个框架。
