Maillet Olivier, Subero Diego, Peltonen Joonas T, Golubev Dmitry S, Pekola Jukka P
QTF Centre of Excellence, Department of Applied Physics, Aalto University School of Science, P.O. Box 13500, 00076, Aalto, Finland.
Nat Commun. 2020 Aug 28;11(1):4326. doi: 10.1038/s41467-020-18163-8.
Heat is detrimental for the operation of quantum systems, yet it fundamentally behaves according to quantum mechanics, being phase coherent and universally quantum-limited regardless of its carriers. Due to their robustness, superconducting circuits integrating dissipative elements are ideal candidates to emulate many-body phenomena in quantum heat transport, hitherto scarcely explored experimentally. However, their ability to tackle the underlying full physical richness is severely hindered by the exclusive use of a magnetic flux as a control parameter and requires complementary approaches. Here, we introduce a dual, magnetic field-free circuit where charge quantization in a superconducting island enables thorough electric field control. We thus tune the thermal conductance, close to its quantum limit, of a single photonic channel between two mesoscopic reservoirs. We observe heat flow oscillations originating from the competition between Cooper-pair tunnelling and Coulomb repulsion in the island, well captured by a simple model. Our results highlight the consequences of charge-phase conjugation on heat transport, with promising applications in thermal management of quantum devices and design of microbolometers.
热对量子系统的运行有害，但它从根本上遵循量子力学，具有相位相干性且无论其载流子如何都普遍受量子限制。由于其稳健性，集成了耗散元件的超导电路是模拟量子热输运中多体现象的理想候选者，然而迄今为止在实验上几乎未被探索。然而，仅使用磁通量作为控制参数严重阻碍了它们处理潜在完整物理丰富性的能力，因此需要互补的方法。在此，我们引入一种无磁场的双电路，其中超导岛中的电荷量子化实现了全面的电场控制。我们由此调节了两个介观储能器之间单个光子通道接近其量子极限的热导率。我们观察到源于岛内库珀对隧穿与库仑排斥之间竞争的热流振荡，一个简单模型能很好地捕捉到这种振荡。我们的结果突出了电荷 - 相位共轭对热输运的影响，在量子器件热管理和微测辐射热计设计方面具有广阔的应用前景。
