编译|未玖
Nature,8 May 2025, Volume 641, Issue 8062
《自然》2025年5月8日，第641卷，8062期
物理学Physics
Quantum twisting microscopy of phonons in twisted bilayer graphene
扭曲双层石墨烯中声子的量子扭曲显微镜
▲ 作者：J. Birkbeck, J. Xiao, A. Inbar, T. Taniguchi, K. Watanabe, E. Berg, et al.
▲链接：
articles/s41586-025-08881-8
▲摘要：
电子和声子之间的耦合是固体中基本相互作用之一，支撑着电阻率、热导性和超导性等广泛现象。然而，直接测量单个声子模式的这种耦合仍颇具挑战。
研究组介绍了一种新型范德华（vdW）材料声子色散和电子-声子耦合（EPC）映射技术。通过将量子扭曲显微镜（QTM）推广到低温，证明了QTM不仅可以通过弹性动量守恒隧穿来映射电子色散，还可以通过非弹性动量守恒隧穿来映射声子色散。至关重要的是，非弹性隧穿强度提供了动量和模式分辨EPC的直接定量度量。
研究组利用该技术测量了扭转角大于6°的扭曲双层石墨烯（TBG）的声子谱和EPC。值得注意的是，不同于与电子耦合随着其动量趋于零而减弱的标准声频声子，TBG呈现出低能模式，其耦合随着扭转角的减小而增加。
研究组证明，这种不寻常的耦合由莫尔系统的层反对称“相位子”模式对层间隧穿的调制引起。该技术为研究与电子隧穿耦合的大量其他中性集体模式开辟了道路，包括量子材料中的等离子体、磁振子和自旋子。
▲ Abstract：
The coupling between electrons and phonons is one of the fundamental interactions in solids, underpinning a wide range of phenomena, such as resistivity, heat conductivity and superconductivity. However, direct measurements of this coupling for individual phonon modes remain a substantial challenge. In this work, we introduce a new technique for mapping phonon dispersions and electron–phonon coupling (EPC) in van der Waals (vdW) materials. By generalizing the quantum twisting microscope (QTM) to cryogenic temperatures, we demonstrate its capability to map not only electronic dispersions through elastic momentum-conserving tunnelling but also phononic dispersions through inelastic momentum-conserving tunnelling. Crucially, the inelastic tunnelling strength provides a direct and quantitative measure of the momentum and mode-resolved EPC. We use this technique to measure the phonon spectrum and EPC of twisted bilayer graphene (TBG) with twist angles larger than 6°. Notably, we find that, unlike standard acoustic phonons, whose coupling to electrons diminishes as their momentum tends to zero, TBG exhibits a low-energy mode whose coupling increases with decreasing twist angle. We show that this unusual coupling arises from the modulation of the interlayer tunnelling by a layer-antisymmetric ‘phason’ mode of the moiré system. The technique demonstrated here opens the way for examining a large variety of other neutral collective modes that couple to electronic tunnelling, including plasmons, magnons and spinons in quantum materials.
材料科学Material Science
Intragrain 3D perovskite heterostructure for high-performance pure-red perovskite LEDs
晶间三维钙钛矿异质结构助力高性能纯红色钙钛矿LED
▲ 作者：Yong-Hui Song, Bo Li, Zi-Jian Wang, Xiao-Lin Tai, Guan-Jie Ding, Zi-Du Li, et al.
▲链接：
articles/s41586-025-08867-6
▲摘要：
金属卤化物钙钛矿是下一代发光二极管（LED）颇有前景的发光候选材料。在纯红色钙钛矿LED（PeLEDs）中同时实现高亮度和高效率是一个持续的目标。
三维CsPbI3-xBrx发射体具有出色的载流子传输能力和高色纯度，可以实现高效和超亮的纯红色PeLED。然而，这种器件容易出现效率骤降，导致在高电流密度下效率低、亮度低。
研究组利用电激发瞬态吸收光谱技术，发现了由空穴泄漏引起的效率骤降。因此，他们开发了CsPbI3-xBrx晶间异质结构，包含窄带隙发射体和宽带隙势垒来限域注入的载流子。通过在[PbX6]4-框架中引入强键合分子来扩展三维CsPbI3-xBrx晶格，从而引入了宽带隙势垒。
该策略产生了明亮高效的纯红色PeLED，具有24600 cd m-2的高亮度，24.2%的峰值外量子效率，以及极低的效率骤降，在22670 cd m-2的高亮度下仍保持10.5%的外量子效率。
▲ Abstract：
metal-halide perovskites are promising light-emitter candidates for next-generation light-emitting diodes (LEDs). Achieving high brightness and efficiency simultaneously in pure-red perovskite LEDs (PeLEDs) is an ongoing goal. Three-dimensional (3D) CsPbI3-xBrx emitters have excellent carrier transport capability and high colour purity, which could allow efficient and ultrabright pure-red PeLEDs. However, such devices are prone to efficiency roll-off, resulting in low efficiency and low brightness under high current density. Here, by using electrically excited transient absorption spectroscopy, we discovered the efficiency roll-off was induced by hole leakage. Therefore, we developed a CsPbI3-xBrx intragrain heterostructure containing narrow bandgap emitters and wide bandgap barriers to confine the injected carriers. The wide bandgap barrier was incorporated by introducing strongly bonding molecules into the [PbX6]4- framework to expand the 3D CsPbI3-xBrx lattice. This strategy resulted in bright and efficient pure-red PeLEDs, with a high brightness of 24,600 cd m-2, maximum external quantum efficiency of 24.2% and low efficiency roll-off, maintaining a 10.5% external quantum efficiency at a high luminance of 22,670 cd m-2.
Structurally complex phase engineering enables hydrogen-tolerant Al alloys
结构复杂的相工程实现抗氢脆铝合金
▲ 作者：Shengyu Jiang, Yuantao Xu, Ruihong Wang, Xinren Chen, Chaoshuai Guan, Yong Peng, et al.
▲链接：
articles/s41586-025-08879-2
▲摘要：
氢脆（HE）降低了铝（Al）合金的耐久性，阻碍了其在氢经济中的应用。铝合金中的金属间化合物颗粒可以捕获氢并减轻HE，但与传统的强化纳米析出相相比，这些颗粒通常以较低的数量密度形成。
研究组报道了在添加Sc的Al-Mg合金中进行尺寸筛选的复杂析出，以实现具有高捕氢能力、高密度分散的细Al3Sc纳米析出相和原位形成的核-壳Al3(Mg,Sc)2/Al3Sc纳米相。两步热处理诱导仅尺寸大于10nm的Al3Sc纳米析出相表面发生Samson相Al3(Mg,Sc)2的非均相形核。
尺寸依赖性与Al3Sc纳米析出相的非共格性有关，这导致镁的局部偏析，并触发Al3(Mg,Sc)2的形成。与无Sc合金相比，Al-Mg-Sc合金中双纳米析出相的定制分布使其强度提高了约40%，抗HE性能提高了近5倍，在H含量高达7 ppmw的铝合金中达到了创纪录的拉伸均匀伸长率。
研究组将此策略应用于其他Al-Mg基合金，如Al-Mg-Ti-Zr、Al-Mg-Cu-Sc和Al-Mg-Zn-Sc合金。该工作展示了一种增加高强度铝合金抗HE的可能途径，且易于适应大规模的工业生产。
▲ Abstract：
Hydrogen embrittlement (HE) impairs the durability of aluminium (Al) alloys and hinders their use in a hydrogen economy. Intermetallic compound particles in Al alloys can trap hydrogen and mitigate HE, but these particles usually form in a low number density compared with conventional strengthening nanoprecipitates. Here we report a size-sieved complex precipitation in Sc-added Al–Mg alloys to achieve a high-density dispersion of both fine Al3Sc nanoprecipitates and in situ formed core-shell Al3(Mg,Sc)2/Al3Sc nanophases with high hydrogen-trapping ability. The two-step heat treatment induces heterogeneous nucleation of the Samson-phase Al3(Mg,Sc)2 on the surface of Al3Sc nanoprecipitates that are only above 10nm in size. The size dependence is associated with Al3Sc nanoprecipitate incoherency, which leads to local segregation of magnesium and triggers the formation of Al3(Mg,Sc)2. The tailored distribution of dual nanoprecipitates in our Al–Mg–Sc alloy provides about a 40% increase in strength and nearly five times improved HE resistance compared with the Sc-free alloy, reaching a record tensile uniform elongation in Al alloys charged with H up to 7ppmw. We apply this strategy to other Al–Mg-based alloys, such as Al–Mg–Ti–Zr, Al–Mg–Cu–Sc and Al–Mg–Zn–Sc alloys. Our work showcases a possible route to increase hydrogen resistance in high-strength Al alloys and could be readily adapted to large-scale industrial production.
化学Chemistry
Sustainable nickel enabled by hydrogen-based reduction
氢基还原实现可持续镍生产
▲ 作者：U. Manzoor, L. Mujica Roncery, D. Raabe I. R. Souza Filho
▲链接：
articles/s41586-025-08901-7
▲摘要：
镍是向可持续能源系统转变的关键因素。到2040年，镍的年需求量预计将超过600万吨，主要由运输部门电气化推动。初级镍生产使用酸和碳基还原剂，每生产一吨镍需排放约20吨二氧化碳。
研究组提出了一种使用无化石氢等离子体还原的方法，从被称为红土的低品位矿石变体中提取镍。他们避开了传统的多步骤工艺，将煅烧、冶炼、还原和精炼整合到一座熔炉内的单一冶金步骤中。该方法以快速还原动力学生产高品位镍铁合金。
通过对炉内气氛的热力学控制，研究组实现了选择性还原镍，得到杂质最少的合金（硅含量 0.04 wt%，磷约0.01 wt%，钙含量 0.09 wt%），而无需进一步精炼。与当前做法相比，该策略有望将能源效率提高约18%，同时直接二氧化碳排放减少高达84%。
因此，该工作表明了一种可持续的策略，有助于缓解镍有益于可持续能源技术与镍生产危害环境之间的矛盾。
▲ Abstract：
Nickel is a critical element in the shift to sustainable energy systems, with the demand for nickel projected to exceed 6 million tons annually by 2040, largely driven by the electrification of the transport sector. Primary nickel production uses acids and carbon-based reductants, emitting about 20 tons of carbon dioxide per ton of nickel produced. Here we present a method using fossil-free hydrogen-plasma-based reduction to extract nickel from low-grade ore variants known as laterites. We bypass the traditional multistep process and combine calcination, smelting, reduction and refining into a single metallurgical step conducted in one furnace. This approach produces high-grade ferronickel alloys at fast reduction kinetics. Thermodynamic control of the atmosphere of the furnace enables selective nickel reduction, yielding an alloy with minimal impurities ( 0.04 wt% silicon, approximately 0.01 wt% phosphorus and 0.09 wt% calcium), eliminating the need for further refining. The proposed method has the potential to be up to about 18% more energy efficient while cutting direct carbon dioxide emissions by up to 84% compared with current practice. Our work thus shows a sustainable approach to help resolve the contradiction between the beneficial use of nickel in sustainable energy technologies and the environmental harm caused by its production.
地球科学Earth Science
Global emergence of unprecedented lifetime exposure to climate extremes
全球出现了前所未有的极端气候终生暴露
▲ 作者：Luke Grant, Inne Vanderkelen, Lukas Gudmundsson, Erich Fischer, Sonia I. Seneviratne Wim Thiery
▲链接：
articles/s41586-025-08907-1
▲摘要：
在人为气候变化的影响下，极端气候正在升级。然而，这如何转化为个体一生中遭遇前所未有的累积极端事件尚不清楚。
研究组使用气候模型、影响模型和人口统计数据来预测在前工业化气候中，经历超过99.99%极端气候累积暴露的人数。他们预计，根据目前的缓解政策（即到2100年，全球变暖路径将比前工业化温度高出2.7℃），从1960年到2020年的出生队列中，面临热浪、农作物歉收、河流洪水、干旱、野火和热带气旋等前所未有气候风险的人口比例至少将翻一番。
在升温1.5℃的路径下，2020年出生人群中将有52%经历前所未有的终生热浪。如果到2100年全球升温达到3.5℃，热浪的比例将上升至92%，农作物歉收的比例将上升至29%，河流洪水的比例将上升至14%。
在社会经济脆弱性高的人群中，面临前所未有终生热浪的概率要大得多。该研究结果呼吁大幅、持续减少温室气体排放，以减轻气候变化给当前年轻一代带来的负担。
▲ Abstract：
Climate extremes are escalating under anthropogenic climate change. Yet, how this translates into unprecedented cumulative extreme event exposure in a person’s lifetime remains unclear. Here we use climate models, impact models and demographic data to project the number of people experiencing cumulative lifetime exposure to climate extremes above the 99.99th percentile of exposure expected in a pre-industrial climate. We project that the birth cohort fraction facing this unprecedented lifetime exposure to heatwaves, crop failures, river floods, droughts, wildfires and tropical cyclones will at least double from 1960 to 2020 under current mitigation policies aligned with a global warming pathway reaching 2.7 °C above pre-industrial temperatures by 2100. Under a 1.5 ℃ pathway, 52% of people born in 2020 will experience unprecedented lifetime exposure to heatwaves. If global warming reaches 3.5 °C by 2100, this fraction rises to 92% for heatwaves, 29% for crop failures and 14% for river floods. The chance of facing unprecedented lifetime exposure to heatwaves is substantially larger among population groups characterized by high socioeconomic vulnerabilities. Our results call for deep and sustained greenhouse gas emissions reductions to lower the burden of climate change on current young generations.
Melt focusing along lithosphere–asthenosphere boundary below Axial volcano
沿轴向火山下方岩石圈-软流圈边界的熔体聚集
▲ 作者：G. M. Kent, A. F. Arnulf, S. C. Singh, H. Carton, A. J. Harding S. Saustrup
▲链接：
articles/s41586-025-08865-8
▲摘要：
在海洋扩张中心之下，岩石圈-软流圈边界（LAB）充当了一个渗透屏障，将地幔深处的熔融物输送到扩张轴。在中速扩张到快速扩张的洋中脊，多通道地震反射技术成像了一个近水平、1~2千米宽的轴向岩浆透镜（AML），其定义了LAB的最上部，但地壳深处LAB的性质仍不确定，地震断层成像只提供了AML下方更宽的低速物质晕的漫反射视图。
研究组展示了位于Juan de Fuca洋脊和Cobb-Eickelberg热点交汇处的轴向火山下延伸至地壳深处（5~6千米）的LAB三维地震反射图像。LAB的三维形态与热控岩浆同化前锋一致，将热点相关和中大洋扩张中心相关的岩浆活动聚集在火山中心，控制了喷发和热液循环以及喷发熔岩的化学成分。
在这种情况下，LAB可被视为“岩浆域”的上表面，即一个熔体驻留的区域（取代了单一“岩浆储层”的概念）。研究组发现了一个漏斗状的地壳LAB，这表明在其他火山系统（如冰岛）中，热控制的岩浆同化可能沿该表面发生。
▲ Abstract：
Beneath oceanic spreading centres, the lithosphere–asthenosphere boundary (LAB) acts as a permeability barrier that focuses the delivery of melt from deep within the mantle towards the spreading axis. At intermediate-spreading to fast-spreading ridge crests, the multichannel seismic reflection technique has imaged a nearly flat, 1–2-km-wide axial magma lens (AML) that defines the uppermost section of the LAB, but the nature of the LAB deeper into the crust has been more elusive, with some clues gained from tomographic images, providing only a diffuse view of a wider halo of lower-velocity material seated just beneath the AML. Here we present 3D seismic reflection images of the LAB extending deep (5–6 km) into the crust beneath Axial volcano, located at the intersection of the Juan de Fuca Ridge and the Cobb–Eickelberg hotspot. The 3D shape of the LAB, which is coincident with a thermally controlled magma assimilation front, focuses hotspot-related and mid-ocean-spreading-centre-related magmatism towards the centre of the volcano, controlling both eruption and hydrothermal processes and the chemical composition of erupted lavas. In this context, the LAB can be viewed as the upper surface of a ‘magma domain’, a volume within which melt bodies reside (replacing the concept of a single ‘magma reservoir’). Our discovery of a funnel-shaped, crustal LAB suggests that thermally controlled magma assimilation could be occurring along this surface at other volcanic systems, such as Iceland.
