Li Hailong, Jiang Hua, Sun Qing-Feng, Xie X C
International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China.
Interdisciplinary Center for Theoretical Physics and Information Sciences (ICTPIS), Fudan University, Shanghai 200433, China; Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai 200433, China.
Sci Bull (Beijing). 2024 May 15;69(9):1221-1227. doi: 10.1016/j.scib.2024.03.024. Epub 2024 Mar 19.
Energy dissipation is of fundamental interest and crucial importance in quantum systems. However, whether energy dissipation can emerge without backscattering inside topological systems remains a question. As a hallmark, we propose a microscopic picture that illustrates energy dissipation in the quantum Hall (QH) plateau regime of graphene. Despite the quantization of Hall, longitudinal, and two-probe resistances (dubbed as the quantum limit), we find that the energy dissipation emerges in the form of Joule heat. It is demonstrated that the non-equilibrium energy distribution of carriers plays much more essential roles than the resistance on energy dissipation. Eventually, we suggest probing the phenomenon by measuring local temperature increases in experiments and reconsidering the dissipation typically ignored in realistic topological circuits.
能量耗散在量子系统中具有根本的重要性和关键意义。然而，在拓扑系统内部，能量耗散是否能够在没有背散射的情况下出现仍是一个问题。作为一个标志，我们提出了一个微观图景，用以说明石墨烯量子霍尔（QH）平台区域中的能量耗散。尽管霍尔电阻、纵向电阻和双探针电阻存在量子化现象（被称为量子极限），但我们发现能量耗散以焦耳热的形式出现。结果表明，载流子的非平衡能量分布在能量耗散方面比电阻起着更为重要的作用。最终，我们建议通过在实验中测量局部温度升高来探测这一现象，并重新考虑在实际拓扑电路中通常被忽略的耗散问题。
