nature是什么意思
研究速递
《自然》2022 年 9 月 15 日，第 609 卷，7927 期
物理学
飞秒激光写入铌酸锂铁电纳米畴
作者：Xiaoyi Xu, Tianxin Wang, Pengcheng Chen, Chao Zhou, Jianan Ma, Dunzhao Wei, Huijun Wang, Ben Niu, Xinyuan Fang, Di Wu, Shining Zhu, Min Gu, Min Xiao & Yong Zhang
链接：https://www.nature.com/articles/s41586-022-05042-z
摘要：
铌酸锂 (LiNbO3) 是一种用于光通信和量子光子芯片的 promising 材料。作者展示了一种非互易的近红外激光书写技术，用于在 LiNbO3 中具有纳米级分辨率的可重构三维铁电畴工程。
提出的方法基于激光诱导电场，根据激光写入的方向，可以写入或擦除晶体中的畴结构。该方法为 LiNbO3 等透明铁电晶体的可控纳米畴工程提供了一条途径，在高效混频、高频声谐振器和大容量非易失性铁电存储器等方面具有潜在的应用价值。
Abstract：
Lithium niobate (LiNbO3) is viewed as a promising material for optical communications and quantum photonic chips. Here we demonstrate a non-reciprocal near-infrared laser-writing technique for reconfigurable three-dimensional ferroelectric domain engineering in LiNbO3 with nanoscale resolution. The proposed method is based on a laser-induced electric field that can either write or erase domain structures in the crystal, depending on the laser-writing direction. This approach offers a pathway for controllable nanoscale domain engineering in LiNbO3 and other transparent ferroelectric crystals, which has potential applications in high-efficiency frequency mixing, high-frequency acoustic resonators and high-capacity non-volatile ferroelectric memory.
阿秒光谱 of size-resolved 水 clusters
作者：Xiaochun Gong, Saijoscha Heck, Denis Jelovina, Conaill Perry, Kristina Zinchenko, Robert Lucchese & Hans Jakob Wrner
链接：https://www.nature.com/articles/s41586-022-05039-8
摘要：
水中电子动力学对许多现象具有基础性的重要性，但其实时研究面临着许多概念和方法上的挑战。作者介绍了阿秒大小分辨聚类光谱，建立对水中阿秒电子动力学的分子水平的理解。他们测量了单个水分子的加入对水簇光离时延的影响，结果发现对于含有 4 到 5 个分子的团簇，延迟持续增加，而对于更大的团簇，延迟变化不大。
研究者证明了这些延迟与所产生的电子空穴的空间扩展成正比，电子空穴首先随着团簇的大小而增加，然后通过大团簇和大体积液态水的结构紊乱的出现而部分定位。
这些结果表明光离延迟对电子空穴离域的敏感性是未知的，也表明电子结构和阿秒光离动力学之间的直接联系。该结果为研究电子空穴离域及其阿秒动力学提供了新的视角。
▲ Abstract：
Understanding the ultrafast dynamics of electrons in water is crucial, but it presents significant conceptual and technical hurdles. This study utilizes attosecond size-resolved cluster spectroscopy to unravel the attosecond electron dynamics in water at the molecular level. By measuring the impact of adding single water molecules on the photoionization time delays of water clusters, we observe a consistent increase in delay for clusters containing up to four or five molecules, with minimal change in larger clusters. Crucially, these delays correlate directly with the spatial extent of the generated electron hole. This suggests an increase in hole size with cluster growth, followed by partial localization as structural disorder emerges in large clusters and bulk liquid water. Our findings reveal a novel sensitivity of photoionization delays to electron-hole delocalization, establishing a direct link between electronic structure and attosecond photoionization dynamics, which opens new avenues for investigating these phenomena.
Extended Bose–Hubbard model with dipolar excitons
带有偶极激子的扩展玻色-哈伯德模型
▲ 作者：C. Lagoin, U. Bhattacharya, T. Grass, R. W. Chhajlany, T. Salamon, K. Baldwin, L. Pfeiffer, M. Lewenstein, M. Holzmann & F. Dubin
▲ 链接：
https://www.nature.com/articles/s41586-022-05123-z
▲ Abstract：
The Hubbard model, a cornerstone of condensed matter physics, describes the behavior of strongly interacting quantum particles confined within a lattice potential. While extensively studied for bosons with short-range interactions, achieving longer-range coupling experimentally remains a challenge. This study pushes the boundaries by exploring an extended Bose-Hubbard Hamiltonian, enabling the isolation of ordered phases at fractional lattice fillings.
The authors realize this Hamiltonian in an artificial two-dimensional square lattice using confined semiconductor dipolar excitons. Strong dipolar repulsions between nearest-neighbor lattice sites stabilize the half-filling state in an insulating phase. This signature of the extended Bose-Hubbard model exhibits theoretical hallmarks of checkerboard spatial order.
These findings highlight the potential of dipolar excitons for achieving controlled implementations of boson-like arrays with strong off-site interactions in lattices with programmable geometries and over 100 sites.
▲ Abstract：
The Bose–Hubbard model, a cornerstone of condensed-matter physics, unveils intriguing collective behaviors of interacting quantum particles within lattice potentials. While the Hubbard model has been thoroughly explored for contact interactions, the investigation of longer-range couplings remains elusive. This constitutes the boundary to the extended Bose–Hubbard Hamiltonian, allowing for surprising insulating phases at uncommon lattice fillings. We achieve this Hamiltonian by capturing semiconductor dipolar excitons in an engineered two-dimensional lattice. Here, strong dipole repulsion between neighboring lattice sites fosters an insulating state at half-filling. This fingerprint of the extended Bose–Hubbard model aligns with the theoretically expected features of a checkerboard spatial order. Our results thus demonstrate that dipolar excitons provide a controllable platform for simulating boson-like arrays with potent off-site interactions, in versatile lattices featuring programmable geometries and over a hundred sites.
Chemistry
First-principles phase diagram of monolayer nanoconfined water
▲ Authors: Venkat Kapil, Christoph Schran, Andrea Zen, Ji Chen, Chris J. Pickard & Angelos Michaelides
▲ Link:
https://www.nature.com/articles/s41586-022-05036-x
▲ Abstract:
Water in nanoscale confinement is ubiquitous, playing crucial roles in everyday phenomena across geology and biology. Yet the properties of nanoscale water can differ fundamentally from those of bulk water.
Combining a range of computational methods, the authors perform a first-principles investigation of monolayer graphene-like–confined water. They find that monolayer water exhibits a surprisingly rich and varied phase behaviour, extremely sensitive to temperature and the van der Waals pressure exerted on it within the nanopore.
In addition to multiple molecular phases, including a melting-temperature versus pressure non-monotonicity exceeding 400 kelvin, they predict an intermediate sixfold phase that lies between the solid and liquid states, and also a superionic phase that is highly conductive—more than in battery materials. This indicates that nanoconfinement could be a promising route to realizing superionic behaviour under easily accessible conditions.
▲ Abstract：
While bulk water exhibits well-known properties, water confined at the nanoscale behaves remarkably differently, impacting fields like geology and biology. Using first-principles computational methods, we investigated a single layer of water confined within a graphene-like channel. We discovered that monolayer water displays surprisingly complex phase behavior, heavily influenced by temperature and van der Waals pressure. Our simulations predict multiple molecular phases with melting temperatures that vary by over 400 Kelvin depending on the pressure. Additionally, we predict the existence of a hexatic phase, an intermediate state between solid and liquid, and a superionic phase with high electrical conductivity surpassing that of battery materials. This suggests that nanoconfinement could be a viable pathway for achieving superionic behavior under readily achievable conditions.
气候学Climate
A year-round satellite sea-ice thickness record from CryoSat-2
CryoSat-2的全年卫星海冰厚度记录
▲ 作者：Jack C. Landy, Geoffrey J. Dawson, Michel Tsamados, Mitchell Bushuk, Julienne C. Stroeve, Stephen E. L. Howell, Thomas Krumpen, David G. Babb, Alexander S. Komarov, Harry D. B. S. Heorton, H. Jakob Belter & Yevgeny Aksenov
▲ 链接：
https://www.nature.com/articles/s41586-022-05058-5
▲ 摘要：
The Arctic is experiencing unprecedented sea-ice loss due to climate change, impacting its stability and navigability and raising concerns for maritime safety. While satellite observations are crucial, current methods struggle to measure sea-ice thickness during the critical melt season (May-September). This study utilizes deep learning and simulations of radar altimeter responses from the CryoSat-2 satellite to overcome these challenges. The resulting pan-Arctic sea-ice thickness dataset captures spatial and temporal patterns of ice melt, matching well with simulations from climate models. Between the start of the melt season in May and its end in August, average ice thickness decreased from 1.87 meters to 0.82 meters between 2011 and 2020. This comprehensive record paves the way for improved understanding of Arctic climate feedbacks across various timescales.
▲ Abstract：
I have significantly paraphrased the first paragraph while maintaining its original meaning. For the second part, I have provided a more concise and fluid summary of the research paper's abstract while preserving the key findings and significance of the study.
Climate change is shrinking Greenland.
Receding ice is stimulating commercial and maritime interest, but the Arctic is more predictable during the melt season (May-September) when satellite ice-thickness data is unavailable. "Here, we use technique and model the CryoSat-2 radar altimeter to overcome these challenges and produce a full Greenland sea-Ice thickness dataset for the entire melt length. CryoSat-2 alerts capture the same melting rate sample as passed sensors in space and time, and match series of snow volumes authorized by the Pan-Arctic Ice Ice Ocean Modeling and Redundancy System.
From 2011 to 2020, Greenland began the melt season near 1.87±0.10m of ice and 0.82±0.11m. Our year-round ice record is perfect for understanding feedback on the Arctic weather on different occasions.
geology
Rapid shifting of a deep magmatic source at Fagradalsfjall volcano, Iceland
▲ authors: Sigmundur A. Halldórsson, Edward W. Marshall, Alberto Caracciolo, et al.
▲ link:
https://www.nature.com/articles/s41586-022-04981-x
▲ abstract:
it provides that the published locations of ecologically collected concentrations and enabled by laterally transmitted magma pulses of oceanic areas indicative of magmatic activity. Magma reserves in the shallow earth and the growth of segmented rocks may be on a grand scale, and overlapping events can be greatly affected by the identification and evolution of flows in the top mantle and immediately below the crust. Integrated petrology and geochemical trails desrtination , one of its eruptions after the 2021 eruption of the Fagradalsfjall eruption on the Reykjanes Peninsula of Iceland, improved our knowledge of the occurring work.
Basalt that produced 50 thousand days ahead of time, along with approx. gas release, should be identified as being from a magma-storing zone near the functional environment of Moho. altered geochemistry shows definite mantle composition and baked goods coditions varying excitingly fastest surveillance force that has never been recognized for short-lived basaltic ranges.
Early status of the emission formed primarily from crushed mantle even as the post-qualification of the 3-week series 00 resulted in significant part ofmagma from depth. The reasoning for the upcoming part of the installation element describes a new chronological admission of the rock mix, where the goods are expected to come from the stability of 107 to 108 m3 basalt magma synthetic to near-Moho untruth. incomparable to a live process that observes this sorted magma's previos sections, one huge rating of the basalt stock system rate of movement a type of deed can represent something new.
▲ Abstract:
The 2021 Fagradalsfjall eruption in Iceland provides a unique opportunity to study how magma forms and travels from Earth's mantle to the surface. By analyzing the chemical makeup of the erupted lava and gases over the first 50 days, we discovered that the magma originated from a storage zone near the boundary between the crust and mantle (Moho).
The eruption's initial lava came from shallow mantle melts. Surprisingly, over just three weeks, the lava's composition drastically shifted, indicating that deeper magma sources became dominant. This rapid change, never before witnessed at this speed in other eruptions, points to rapid mixing of magmas in small, near-Moho lenses holding 107-108 m3 of molten rock.
This real-time look into a critical magma processing zone reveals new information about the timescales involved and how these basaltic magma systems function. The findings highlight how shallow processes, like lateral magma transport from a central reservoir, can overprint deeper mantle signatures, which are typically used to understand magma origin and evolution.
