Nature, Volume 639 Issue 8054, 13 March 2025
《自然》第639卷,8054期,2025年3月13日
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物理学Physics
Continuous-variable multipartite entanglement in an integrated microcomb
集成微梳中的连续变量多部纠缠
▲ 作者:Xinyu Jia, Chonghao Zhai, Xuezhi Zhu, Chang You, Yunyun Cao, Xuguang Zhang, Yun Zheng, Zhaorong Fu, Jun Mao, Tianxiang Dai, Lin Chang, Xiaolong Su, Qihuang Gong Jianwei Wang
▲链接:
articles/s41586-025-08602-1
▲摘要:
大尺度纠缠态的产生对于量子计算、量子通信、量子计量等量子技术至关重要。集成量子光子学能够在芯片上对量子光态进行编码、处理和检测,为大规模纠缠态的产生和操纵提供了一个很有前途的平台。在单光子内以离散变量编码的量子比特之间产生纠缠是具有挑战性的,因为在光子芯片上使单光子相互作用是困难的。使用连续变量操作的设备更有前途,因为它们能够确定地产生和纠缠模,其中信息以光正交编码。
迄今为止的演示仅限于两个模之间的纠缠。研究者报告了在集成光学芯片上连续可变八模纠缠的确定性产生。该芯片提供了一个量子微梳,可以产生低于阈值的多模压缩真空光学频率梳。他们验证了八模态的不可分性,并通过违反van Loock–Furusawa标准,证明了数百兆赫边带频率上的超模多部纠缠。
通过测量具有足够低的非对角噪声的抵消相关的完整矩阵,研究者描述了多部纠缠结构,它近似于有限压缩的预期簇型结构。这项工作显示了连续变量集成光子量子器件在促进量子计算、网络和传感方面的潜力。
▲ Abstract:
The generation of large-scale entangled states is crucial for quantum technologies, such as quantum computation, communication and metrology. Integrated quantum photonics that enables on-chip encoding, processing and detection of quantum light states offers a promising platform for the generation and manipulation of large-scale entangled states4,5. Generating entanglement between qubits encoded in discrete variables within single photons is challenging, owing to the difficulty of making single photons interact on photonic chips. Devices that operate with continuous variables are more promising, as they enable the deterministic generation and entanglement of qumodes, in which information is encoded in light quadratures. Demonstrations so far have been limited to entanglement between two qumodes. Here we report the deterministic generation of a continuous-variable eight-mode entanglement on an integrated optical chip. The chip delivers a quantum microcomb that produces multimode squeezed-vacuum optical frequency combs below the threshold. We verify the inseparability of our eight-mode state and demonstrate supermode multipartite entanglement over hundreds of megahertz sideband frequencies through violation of the van Loock–Furusawa criteria. By measuring the full matrices of nullifier correlations with sufficiently low off-diagonal noises, we characterize multipartite entanglement structures, which are approximate to the expected cluster-type structures for finite squeezing. This work shows the potential of continuous-variable integrated photonic quantum devices for facilitating quantum computing, networking and sensing.
An operating system for executing applications on quantum network nodes
用于在量子网络节点上执行应用程序的操作系统
▲ 作者:C. Delle Donne, M. Iuliano, B. van der Vecht, G. M. Ferreira, H. Jirovská, T. J. W. van der Steenhoven, A. Dahlberg, M. Skrzypczyk, D. Fioretto, M. Teller, P. Filippov, A. R.-P. Montblanch, J. Fischer, H. B. van Ommen, N. Demetriou, D. Leichtle, L. Music, H. Ollivier, I. te Raa, W. Kozlowski, T. H. Taminiau, P. Pawe?czak, T. E. Northup, R. Hanson S. Wehner
▲链接:
articles/s41586-025-08704-w
▲摘要:
未来量子网络的目标是实现仅使用经典通信无法实现的新互联网应用。到目前为止,量子处理器上的量子网络应用和功能的演示已经在特定于实验设置的特设软件中进行,编程为使用实验物理专业知识直接在低级控制设备中执行单个任务(应用实验)。
研究者报告了一种架构的设计和实现,该架构能够在与平台无关的高级软件中的量子处理器上执行量子网络应用程序。他们通过将其实现为量子网络操作系统,并执行测试程序,展示了该架构在高级软件中执行应用程序的能力,包括在基于金刚石中的氮空位中心的两个量子网络节点上从客户端到服务器的委托计算。研究者展示了该架构如何通过多任务处理不同的应用程序来最大限度地利用量子网络硬件。
该体系结构可用于在与该系统模型相对应的任何量子处理器平台上执行程序。研究者通过为基于单个40Ca+原子的捕获离子量子网络节点演示QNodeOS的额外驱动程序来说明这一点。该架构为量子网络编程的计算机科学研究奠定了基础,并为将量子网络技术带入社会的软件开发铺平了道路。
▲ Abstract:
The goal of future quantum networks is to enable new internet applications that are impossible to achieve using only classical communication. Up to now, demonstrations of quantum network applications and functionalities on quantum processors have been performed in ad hoc software that was specific to the experimental setup, programmed to perform one single task (the application experiment) directly into low-level control devices using expertise in experimental physics. Here we report on the design and implementation of an architecture capable of executing quantum network applications on quantum processors in platform-independent high-level software. We demonstrate the capability of the architecture to execute applications in high-level software by implementing it as a quantum network operating system—QNodeOS—and executing test programs, including a delegated computation from a client to a server on two quantum network nodes based on nitrogen-vacancy (NV) centres in diamond. We show how our architecture allows us to maximize the use of quantum network hardware by multitasking different applications. Our architecture can be used to execute programs on any quantum processor platform corresponding to our system model, which we illustrate by demonstrating an extra driver for QNodeOS for a trapped-ion quantum network node based on a single 40Ca+ atom16. Our architecture lays the groundwork for computer science research in quantum network programming and paves the way for the development of software that can bring quantum network technology to society.
化学Chemistry
Methane oxidation to ethanol by a molecular junction photocatalyst
用分子结光催化剂将甲烷氧化为乙醇
▲ 作者:Jijia Xie, Cong Fu, Matthew G. Quesne, Jian Guo, Chao Wang, Lunqiao Xiong, Christopher D. Windle, Srinivas Gadipelli, Zheng Xiao Guo, Weixin Huang, C. Richard A. Catlow Junwang Tang
▲链接:
articles/s41586-025-08630-x
▲摘要:
甲烷是天然气和页岩气的主要成分,是化学合成的重要碳源。甲烷在温和条件下直接部分氧化为液态氧是一种有吸引力的途径,但分子的惰性使得同时实现对单一目标产物的高转化率和高选择性具有挑战性。当瞄准需要C-C耦合的更有价值的产品时,这种困难会被放大。
虽然选择性部分甲烷氧化过程通常产生C1氧合物,但最近的报告记录了光催化甲烷转化为C2氧合物乙醇,转化率低,但选择性好到高。研究表明,具有苯和三嗪交替基序的共价三嗪基框架-1分子内结光催化剂以高选择性和显著提高的转化率驱动甲烷偶联和氧化成乙醇。异质结结构不仅能使电荷在生成后高效、长时间的分离,还能使水和氧分别优先吸附在三嗪和苯基上。
这种双位点特征将C-C偶联从形成·OH自由基的位点分离成乙烷中间体,从而避免过度氧化。当负载Pt以进一步提高性能时,分子异质结光催化剂在填充床流动反应器中生成乙醇,转化率大大提高,表观量子效率达到9.4%。研究者推测,进一步发展“分子内连接”方法将为C-C偶联提供高效和选择性的催化剂,包括但不限于甲烷转化为C2+化学品。
▲ Abstract:
Methane, the main component of natural and shale gas, is a significant carbon source for chemical synthesis. The direct partial oxidation of methane to liquid oxygenates under mild conditions is an attractive pathway, but the inertness of the molecule makes it challenging to achieve simultaneously high conversion and high selectivity towards a single target product. This difficulty is amplified when aiming for more valuable products that require C–C coupling. Whereas selective partial methane oxidation processes have thus typically generated C1 oxygenates, recent reports have documented photocatalytic methane conversion to the C2 oxygenate ethanol with low conversions but good-to-high selectivities. Here we show that the intramolecular junction photocatalyst covalent triazine-based framework-1 with alternating benzene and triazine motifs drives methane coupling and oxidation to ethanol with a high selectivity and significantly improved conversion. The heterojunction architecture not only enables efficient and long-lived separation of charges after their generation, but also preferential adsorption of H2O and O2 to the triazine and benzene units, respectively. This dual-site feature separates C–C coupling to form ethane intermediates from the sites where ·OH radicals are formed, thereby avoiding over-oxidation. When loaded with Pt to further boost performance, the molecular heterojunction photocatalyst generates ethanol in a packed-bed flow reactor with greatly improved conversion that results in an apparent quantum efficiency of 9.4%. We anticipate that further developing the ‘intramolecular junction’ approach will deliver efficient and selective catalysts for C–C coupling, pertaining, but not limited, to methane conversion to C2+ chemicals.
10,000-h-stable intermittent alkaline seawater electrolysis
稳定间歇式碱性海水电解
▲ 作者:Qihao Sha, Shiyuan Wang, Li Yan, Yisui Feng, Zhuang Zhang, Shihang Li, Xinlong Guo, Tianshui Li, Hui Li, Zhongbin Zhuang, Daojin Zhou, Bin Liu Xiaoming Sun
▲链接:
articles/s41586-025-08610-1
▲摘要:
由可再生电力驱动的海水电解为生产绿色氢提供了一个有吸引力的策略。然而,海水直接电解面临着许多挑战,主要是由于海水中大量卤化物离子(Cl?,Br?)引起的腐蚀和阳极竞争反应。
以往对海水电解的研究主要集中在阳极的开发上。因为阴极在还原电位下工作,在海水电解过程中不受电极溶解或氯化物腐蚀反应的影响。然而,可再生能源是间歇性的、可变的和随机的。如果使用可再生电力驱动海水电解,会导致频繁的启停操作。
研究者首先揭示了间歇电解过程中海水分裂阴极的动态演化和降解过程,并在此基础上提出了构建催化剂钝化层来维持其运行过程中的析氢性能。在NiCoP-Cr2O3阴极表面原位形成的磷酸盐钝化层可以有效地保护金属活性位点在频繁放电过程中不被氧化,并在关闭条件下阻止阴极上的卤化物离子吸附。
研究证明,使用这种设计策略优化的电极可以在碱性海水中承受0.5 A cm?2的波动操作10,000小时,电压增长率仅为0.5% khr?1。这一策略为促进可再生电力驱动的实用海水分解技术的发展提供了新的见解。
▲ Abstract:
Seawater electrolysis powered by renewable electricity provides an attractive strategy for producing green hydrogen. However, direct seawater electrolysis faces many challenges, primarily arising from corrosion and competing reactions at the anode caused by the abundance of halide ions (Cl?, Br?) in seawater. Previous studies on seawater electrolysis have mainly focused on the anode development, because the cathode operates at reducing potentials, which is not subject to electrode dissolution or chloride corrosion reactions during seawater electrolysis. However, renewable energy sources are intermittent, variable and random, which cause frequent start–shutdown operations if renewable electricity is used to drive seawater electrolysis. Here we first unveil dynamic evolution and degradation of seawater splitting cathode in intermittent electrolysis and, accordingly, propose construction of a catalyst’s passivation layer to maintain the hydrogen evolution performance during operation. An in situ-formed phosphate passivation layer on the surface of NiCoP–Cr2O3cathode can effectively protect metal active sites against oxidation during frequent discharge processes and repel halide ion adsorption on the cathode during shutdown conditions. We demonstrate that electrodes optimized using this design strategy can withstand fluctuating operation at 0.5?A?cm?2 for 10,000?h in alkaline seawater, with a voltage increase rate of only 0.5% khr?1. The newly discovered challenge and our proposed strategy herein offer new insights to facilitate the development of practical seawater splitting technologies powered by renewable electricity.
生态Ecology
Community estimate of global glacier mass changes from 2000 to 2023
2000年—2023年全球冰川质量变化的群落估计
▲ 作者:The GlaMBIE Team
▲链接:
articles/s41586-024-08545-z
▲摘要:
冰川是持续的人为气候变化的指标。它们的融化导致当地地质灾害增加,并影响海洋和陆地生态系统、区域淡水资源以及全球水和能源循环。冰川与格陵兰岛和南极冰盖一起,是当前和未来海平面上升的重要驱动因素。以往对全球冰川质量变化的评估受到时空限制和现有数据序列的异质性的阻碍。
研究者通过一项相互比较研究表明,从2000年到2023年,全球冰川每年损失273±160亿吨质量,从前半期(2000年—2011年)到后半期(2012年—2023年)增加了36±10%。自2000年以来,冰川的区域冰量减少了2%至39%,全球冰量减少了约5%。冰川质量损失大约比格陵兰冰盖损失大18%,是南极冰盖损失的两倍多。
该研究结果来自科学界的努力,收集、均匀化、组合和分析来自原位和遥感观测的冰川质量变化。尽管该评估与以前在全球尺度上的评估结果一致,但由于观测方法之间的系统差异,作者发现一些较大的区域偏差。研究为更好地理解观测差异和校准模式组合提供了一个精细的基线,这将有助于缩小21世纪的预估不确定性。
▲ Abstract:
Glaciers are indicators of ongoing anthropogenic climate change. Their melting leads to increased local geohazards, and impacts marine and terrestrial4,5 ecosystems, regional freshwater resources, and both global water and energy cycles. Together with the Greenland and Antarctic ice sheets, glaciers are essential drivers of present and future sea-level rise. Previous assessments of global glacier mass changes have been hampered by spatial and temporal limitations and the heterogeneity of existing data series. Here we show in an intercomparison exercise that glaciers worldwide lost 273?±?16?gigatonnes in mass annually from 2000 to 2023, with an increase of 36?±?10% from the first (2000–2011) to the second (2012–2023) half of the period. Since 2000, glaciers have lost between 2% and 39% of their ice regionally and about 5% globally. Glacier mass loss is about 18% larger than the loss from the Greenland Ice Sheet and more than twice that from the Antarctic Ice Sheet. Our results arise from a scientific community effort to collect, homogenize, combine and analyse glacier mass changes from in situ and remote-sensing observations. Although our estimates are in agreement with findings from previous assessments at a global scale, we found some large regional deviations owing to systematic differences among observation methods. Our results provide a refined baseline for better understanding observational differences and for calibrating model ensembles, which will help to narrow projection uncertainty for the twenty-first century.
Global biodiversity loss from outsourced deforestation
外包毁林造成的全球生物多样性损失
▲ 作者:R. Alex Wiebe David S. Wilcove
▲链接:
articles/s41586-024-08569-5
▲摘要:
全球化使各国能够将土地使用的环境成本日益外部化,包括生物多样性的丧失。到目前为止,科学界对国家如何通过对其他国家种植的农业和林业产品的需求而导致其境外生物多样性丧失的了解非常不全面。研究者通过24个发达国家对通过全球供应链获得的产品的消费,量化了2001年至2015年全球森林脊椎动物因毁林造成的范围损失。
该研究表明,这些驱动型国家对其境内以外物种的累积范围损失负有更大的责任。这些国际影响在地理上集中,使他们能够绘制出生物多样性外包损失的全球热点。国家对附近地区物种的外部影响最大。然而,在少数情况下,发达国家也对遥远国家的脊椎动物造成了不成比例的伤害。
▲ Abstract:
Globalization increasingly allows countries to externalize the environmental costs of land use, including biodiversity loss1. So far, we have a very incomplete understanding of how countries cause biodiversity loss outside their own borders through their demand for agricultural and forestry products grown in other countries2. Here we quantify the global range losses to forest vertebrates from 2001 to 2015 caused by deforestation attributable to 24 developed countries by means of their consumption of products obtained through global supply chains. We show that these driver countries are responsible for much greater cumulative range loss to species outside their own borders than within them. These international impacts were concentrated geographically, allowing us to map global hotspots of outsourced losses of biodiversity. Countries had the greatest external impacts on species occurring in nearby regions. However, in a few cases, developed countries also inflicted disproportionate harm on vertebrates in distant countries.
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