近日，美国麻省理工学院Pablo Jarillo-Herrero团队研究了莫尔石墨烯中节点超导间隙的实验证据。这一研究成果于2025年11月6日发表在《科学》杂志上。

理解魔角石墨烯的超导性质仍然具有挑战性。一个关键的困难在于在这个强相互作用的系统中识别不同的能量尺度，特别是超导间隙。

研究组报道了魔角扭曲三层石墨烯的隧道光谱和输运测量。这种方法使他们能够确定两个不同能量尺度共存的v形隧道隙：一个明显的低能超导隙，在超导临界温度和磁场下消失，以及一个高能量赝隙。超导隧穿光谱随温度和磁场的变化表现出线性的隙填充行为，并表现出与节点序参数一致的Volovik效应。该工作表明了超导间隙的非常规性质，并为可调谐量子材料的多维研究建立了一个实验框架。

附：英文原文

Title: Experimental evidence for nodal superconducting gap in moiré graphene

Author: Jeong Min Park, Shuwen Sun, Kenji Watanabe, Takashi Taniguchi, Pablo Jarillo-Herrero

Issue&Volume: 2025-11-06

Abstract: Understanding the nature of superconductivity in magic-angle graphene remains challenging. A key difficulty lies in discerning the different energy scales in this strongly interacting system, particularly the superconducting gap. Here, we report simultaneous tunneling spectroscopy and transport measurements of magic-angle twisted trilayer graphene. This approach allows us to identify two coexisting V-shaped tunneling gaps with different energy scales: a distinct low-energy superconducting gap that vanishes at the superconducting critical temperature and magnetic field, and a higher-energy pseudogap. The superconducting tunneling spectra display a linear gap-filling behavior with temperature and magnetic field and exhibit the Volovik effect, consistent with a nodal order parameter. Our work suggests an unconventional nature of the superconducting gap and establishes an experimental framework for multidimensional investigation of tunable quantum materials.

DOI: adv8376

Source: https://www.science.org/doi/10.1126/science.adv8376