近日，北京大学的谢心澄及其研究小组与复旦大学的江华等人合作并取得一项新进展。经过不懈努力，他们揭示量子极限下的涌现能量耗散现象。相关研究成果已于2024年3月19日在国际知名学术期刊《科学通报》上发表。

作为一个标志，该研究团队提出了一个微观图，用于阐明石墨烯量子霍尔(QH)平台状态下的能量耗散。尽管霍尔电阻、纵向电阻和双探针电阻都呈现出量子化特征，即达到了所谓的“量子极限”，但研究人员发现能量耗散主要以焦耳热的形式存在。进一步的研究表明，载流子的非平衡能量分布对能量耗散的影响远超阻力。因此，研究人员建议通过测量实验中的局部温度升高来探测这一现象，并重新考虑了在实际拓扑电路中通常被忽略的耗散问题。

据悉，在量子系统中，能量耗散是一个非常重要的问题。然而，在拓扑系统内部是否能在没有反向散射的情况下产生能量耗散仍然是一个问题。

附：英文原文

Title: Emergent energy dissipation in quantum limit

Author: Hailong Li, Hua Jiang, Qing-Feng Sun, X.C. Xie

Issue&Volume: 2024/03/19

Abstract: 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.

DOI: 10.1016/j.scib.2024.03.024

Source: https://www.sciencedirect.com/science/article/abs/pii/S2095927324001683