《自然》（20240509出版）一周論文導讀

Nature, 9 May 2024, Volume 629 Issue 8011

《自然》2024年5月9日，第629卷，8011期

物理學Physics

Venus water loss is dominated by HCO+ dissociative recombination

金星失水主要是由HCO+解離復合引起的

▲ 作者：M. S. Chaffin, E. M. Cangi, B. S. Gregory, R. V. Yelle, J. Deighan, R. D. Elliott & H. Gr?ller

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07261-y

▲ 摘要：

盡管金星的大小和物質來源與地球相似，但它極其干燥，這表明幾乎所有的水都是通過氫氣從古老的蒸汽為主的大氣中流出而流失到太空中的。這種流體動力學逃逸很可能移除了最初類似地球的3公里全球等效層（GEL）的大部分水，但不能將大氣消耗到目前觀測到的3厘米的GEL，因為它在大約10~100米的GEL以下關閉。

為了使金星上的水完全流失，并使觀測到的大量大氣中氘的富集量達到地球的120倍，需要有至今仍在運行的非熱氫逸出機制。早期的研究將這些因素確定為共振電荷交換、熱氧沖擊和離子流出，建立了氫逸出的共識觀點，此后只有很少的更新。

我們的研究表明這一共識忽略了最重要的現今氫損失過程，HCO+解離重組。這一過程幾乎使金星H的逃逸率增加了1倍，因此，維持穩定的大氣水豐度所需的火山水排放和/或撞擊物的數量也增加了1倍。

這些較高的損失率解決了在同時解釋金星水的測量豐度和同位素比率方面長期存在的困難，并將在推測的晚期海洋情景之后加速干燥。由于設計上的限制，過去的金星任務無法同時測量HCO+和由其重組產生的逃逸氫，未來的航天器測量是必要的。

▲ Abstract：

Despite its Earth-like size and source material, Venus is extremely dry, indicating near-total water loss to space by means of hydrogen outflow from an ancient, steam-dominated atmosphere. Such hydrodynamic escape likely removed most of an initial Earth-like 3-km global equivalent layer (GEL) of water but cannot deplete the atmosphere to the observed 3-cm GEL because it shuts down below about 10–100?m GEL. To complete Venus water loss, and to produce the observed bulk atmospheric enrichment in deuterium of about 120?times Earth, nonthermal H escape mechanisms still operating today are required. Early studies identified these as resonant charge exchange, hot oxygen impact and ion outflow, establishing a consensus view of H escape that has since received only minimal updates. Here we show that this consensus omits the most important present-day H loss process, HCO+ dissociative recombination. This process nearly doubles the Venus H escape rate and, consequently, doubles the amount of present-day volcanic water outgassing and/or impactor infall required to maintain a steady-state atmospheric water abundance. These higher loss rates resolve long-standing difficulties in simultaneously explaining the measured abundance and isotope ratio of Venusian water and would enable faster desiccation in the wake of speculative late ocean scenarios. Design limitations prevented past Venus missions from measuring both HCO+ and the escaping hydrogen produced by its recombination; future spacecraft measurements are imperative.

An atomic boson sampler

原子玻色子采樣器

▲ 作者：Aaron W. Young, Shawn Geller, William J. Eckner, Nathan Schine, Scott Glancy, Emanuel Knill & Adam M. Kaufman

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07304-4

▲ 摘要：

玻色子采樣器實現了量子計算的受限模型。它是由根據可編程的、非相互作用的動力學傳播的相同玻色子的干涉所產生的分布的采樣能力來定義的。有效的精確的經典玻色子采樣模擬被認為是不存在的，這激發了光子越來越多的光子學中突破性的玻色子采樣實驗。

然而，很難產生和可靠地進化特定數量的低損耗光子，因此通常使用概率技術進行后選擇或標記改變標準玻色子采樣。

我們通過在二維隧道耦合光學晶格中使用超冷原子實現玻色子采樣來解決上述挑戰。這一演示是由一種以前未實現的工具組合實現的，包括高保真光學冷卻和晶格中原子的成像，以及使用光學鑷子對這些原子進行可編程控制。當擴展到相互作用系統時，我們的研究證明了在各種哈伯德模型的模擬中直接組裝基態和激發態所需的核心能力。

▲ Abstract：

A boson sampler implements a restricted model of quantum computing. It is defined by the ability to sample from the distribution resulting from the interference of identical bosons propagating according to programmable, non-interacting dynamics. An efficient exact classical simulation of boson sampling is not believed to exist, which has motivated ground-breaking boson sampling experiments in photonics with increasingly many photons. However, it is difficult to generate and reliably evolve specific numbers of photons with low loss, and thus probabilistic techniques for postselection or marked changes to standard boson sampling are generally used. Here, we address the above challenges by implementing boson sampling using ultracold atoms in a two-dimensional, tunnel-coupled optical lattice. This demonstration is enabled by a previously unrealized combination of tools involving high-fidelity optical cooling and imaging of atoms in a lattice, as well as programmable control of those atoms using optical tweezers. When extended to interacting systems, our work demonstrates the core abilities required to directly assemble ground and excited states in simulations of various Hubbard models.

Observation of Nagaoka polarons in a Fermi–Hubbard quantum simulator

費米—哈伯德量子模擬器中長岡極化子的觀測

▲ 作者：Martin Lebrat, Muqing Xu, Lev Haldar Kendrick, Anant Kale, Youqi Gang, Pranav Seetharaman, Ivan Morera, Ehsan Khatami, Eugene Demler和Markus Greiner

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07272-9

▲ 摘要：

量子干涉可以深刻地改變物質的多體相的性質。在哈伯德模型中，長岡證明了引入單個流動電荷可以通過路徑干擾將順磁絕緣體轉變為鐵磁體。然而，由單獨成像的摻雜劑引起的這種動力學磁性的微觀觀察迄今為止還難以捉摸。我們證明了長岡極化子在一個三角形光學晶格中用強相互作用費米子實現的哈伯德系統中的出現。

利用量子氣體顯微鏡，我們將這些極化子成像為粒子摻雜劑周圍的擴展鐵磁氣泡，這些氣泡是由相干摻雜劑運動和自旋交換的局部相互作用產生的。

相比之下，由于三角形幾何結構引起的動力學挫折促進了空穴摻雜劑周圍的反鐵磁極化子。我們的工作預示著探索由強相關系統和超大尺寸的電荷運動驅動的奇異量子相，這對數值模擬具有挑戰性。

▲ Abstract：

Quantum interference can deeply alter the nature of many-body phases of matter. In the case of the Hubbard model, Nagaoka proved that introducing a single itinerant charge can transform a paramagnetic insulator into a ferromagnet through path interference. However, a microscopic observation of this kinetic magnetism induced by individually imaged dopants has been so far elusive. Here we demonstrate the emergence of Nagaoka polarons in a Hubbard system realized with strongly interacting fermions in a triangular optical lattice. Using quantum gas microscopy, we image these polarons as extended ferromagnetic bubbles around particle dopants arising from the local interplay of coherent dopant motion and spin exchange. By contrast, kinetic frustration due to the triangular geometry promotes antiferromagnetic polarons around hole dopants. Our work augurs the exploration of exotic quantum phases driven by charge motion in strongly correlated systems and over sizes that are challenging for numerical simulation.

化學Chemistry

Multi-project wafers for flexible thin-film electronics by independent foundries

由獨立代工廠生產的柔性薄膜電子產品的多項目晶圓

▲ 作者：Hikmet ?eliker, Wim Dehaene & Kris Myny

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07306-2

▲ 摘要：

柔性和大面積電子產品依靠薄膜晶體管（TFT）來制造顯示器、大面積圖像傳感器、微處理器、可穿戴醫療貼片、數字微流體等。雖然硅基互補金屬氧化物半導體（CMOS）芯片是在一個晶圓上使用多個芯片制造的，而且多項目晶圓概念可以在同一個晶圓內聚集各種CMOS芯片設計，但TFT制造目前缺乏一種完全驗證的通用設計方法。

這增加了制造基于TFT的柔性電子產品的成本和復雜性，減緩了它們與更成熟應用的集成，并限制了代工廠可實現的設計復雜性。

我們展示了一個穩定的、高產量的TFT平臺，用于兩種主流TFT技術的無晶圓制造，即基于晶圓的非晶銦鎵鋅氧化物和基于面板的低溫多晶硅，這兩種關鍵的TFT技術適用于柔性襯底。

我們在這兩種技術中設計了標志性的6502微處理器，作為演示和擴展多項目晶圓方法的用例。啟用TFT的代工模型，作為硅CMOS技術的類比，可以加速基于這些器件的應用和技術的增長和發展。

▲ Abstract：

Flexible and large-area electronics rely on thin-film transistors (TFTs) to make displays, large-area image sensors, microprocessors, wearable healthcare patches, digital microfluidics and more. Although silicon-based complementary metal–oxide–semiconductor (CMOS) chips are manufactured using several dies on a single wafer and the multi-project wafer concept enables the aggregation of various CMOS chip designs within the same die, TFT fabrication is currently lacking a fully verified, universal design approach. This increases the cost and complexity of manufacturing TFT-based flexible electronics, slowing down their integration into more mature applications and limiting the design complexity achievable by foundries. Here we show a stable and high-yield TFT platform for the fabless manufacturing of two mainstream TFT technologies, wafer-based amorphous indium–gallium–zinc oxide and panel-based low-temperature polycrystalline silicon, two key TFT technologies applicable to flexible substrates. We have designed the iconic 6502 microprocessor in both technologies as a use case to demonstrate and expand the multi-project wafer approach. Enabling the foundry model for TFTs, as an analogy of silicon CMOS technologies, can accelerate the growth and development of applications and technologies based on these devices.

Chemical short-range disorder in lithium oxide cathodes

鋰氧化物陰極的化學短程失序

▲ 作者：Qidi Wang, Zhenpeng Yao, Jianlin Wang, Hao Guo, Chao Li, Dong Zhou, Xuedong Bai, Hong Li, Baohua Li, Marnix Wagemaker & Chenglong Zhao

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07362-8

▲ 摘要：

有序層狀結構是鋰離子陰極的重要組成部分。然而，在充電時，固有的脆弱的缺鋰框架容易受到晶格應變和結構和/或化學機械退化的影響，導致容量迅速退化，從而縮短電池壽命。

我們報告了一種解決這些問題的方法，該方法使用化學短程無序（CSRD）集成到氧化物陰極中，該方法涉及晶格中元素在空間維度上的局部分布，跨越幾個最近鄰的間隔。這是在結構化學基本原理的指導下，通過改進的陶瓷合成工藝實現的。

為了證明其可行性，我們展示了CSRD的引入如何實質性地影響層狀鋰鈷氧化物陰極的晶體結構。這表現在過渡金屬環境及其與氧的相互作用中，有效地防止了晶體板在除鋰過程中的有害滑動和結構惡化。同時影響電子結構，提高電子導電性。這些特性對鋰離子存儲能力非常有利，顯著提高了循環壽命和倍率能力。

此外，我們發現CSRD可以通過改進的化學共摻雜引入到其他層狀氧化物材料中，進一步說明了其提高結構和電化學穩定性的潛力。這些發現為氧化物陰極的設計開辟了新的途徑，為CSRD對先進功能材料的晶體和電子結構的影響提供了見解。

▲ Abstract：

Ordered layered structures serve as essential components in lithium (Li)-ion cathodes1,2,3. However, on charging, the inherently delicate Li-deficient frameworks become vulnerable to lattice strain and structural and/or chemo-mechanical degradation, resulting in rapid capacity deterioration and thus short battery life2,4. Here we report an approach that addresses these issues using the integration of chemical short-range disorder (CSRD) into oxide cathodes, which involves the localized distribution of elements in a crystalline lattice over spatial dimensions, spanning a few nearest-neighbour spacings. This is guided by fundamental principles of structural chemistry and achieved through an improved ceramic synthesis process. To demonstrate its viability, we showcase how the introduction of CSRD substantially affects the crystal structure of layered Li cobalt oxide cathodes. This is manifested in the transition metal environment and its interactions with oxygen, effectively preventing detrimental sliding of crystal slabs and structural deterioration during Li removal. Meanwhile, it affects the electronic structure, leading to improved electronic conductivity. These attributes are highly beneficial for Li-ion storage capabilities, markedly improving cycle life and rate capability. Moreover, we find that CSRD can be introduced in additional layered oxide materials through improved chemical co-doping, further illustrating its potential to enhance structural and electrochemical stability. These findings open up new avenues for the design of oxide cathodes, offering insights into the effects of CSRD on the crystal and electronic structure of advanced functional materials.

Growth of diamond in liquid metal at 1 atm pressure

金剛石在1atm壓力下在液態金屬中的生長

▲ 作者：Yan Gong, Da Luo, Myeonggi Choe, Yongchul Kim, Babu Ram, Mohammad Zafari, Won Kyung Seong, Pavel Bakharev, Meihui Wang, In Kee Park, Seulyi Lee, Tae Joo Shin, Zonghoon Lee, Geunsik Lee & Rodney S. Ruoff

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07339-7

▲ 摘要：

天然鉆石是在幾十億年前地球上地幔的金屬熔體中形成的，溫度為900~ 1400°C，壓力為5—6 GPa。根據碳3的相圖，金剛石在高壓和高溫條件下是熱力學穩定的。

1955年，通用電氣公司的科學家們發明并使用了高壓高溫設備，利用約7gpa和1600°C的硫化鐵熔融來合成鉆石。有一種現有的模型認為，金剛石只能在高壓和高溫下用液態金屬生長。我們描述了使用液態金屬在1atm壓力和1025°C下生長無種子顆粒的金剛石晶體和多晶金剛石薄膜，打破了這種模式。

金剛石生長在由鎵、鐵、鎳和硅組成的液態金屬的地下，是通過甲烷的催化活化和碳原子向地下區域內擴散而形成的。我們發現碳在液態金屬亞表面的過飽和導致了金剛石的成核和生長，其中Si在穩定四價鍵碳簇中起著重要的作用，而四價鍵碳簇在成核中起著重要的作用。

在中等溫度和1atm壓力下在液態金屬中生長（亞穩態）金剛石，為進一步的基礎科學研究和這種生長的尺度化開辟了許多可能性。

▲ Abstract：

Natural diamonds were (and are) formed (thousands of million years ago) in the upper mantle of Earth in metallic melts at temperatures of 900–1,400?°C and at pressures of 5–6?GPa (refs.?1,2). Diamond is thermodynamically stable under high-pressure and high-temperature conditions as per the phase diagram of carbon3. Scientists at General Electric invented and used a high-pressure and high-temperature apparatus in 1955 to synthesize diamonds by using molten iron sulfide at about 7?GPa and 1,600?°C (refs.?4,5,6). There is an existing model that diamond can be grown using liquid metals only at both high pressure and high temperature7. Here we describe the growth of diamond crystals and polycrystalline diamond films with no seed particles using liquid metal but at 1?atm pressure and at 1,025?°C, breaking this pattern. Diamond grew in the subsurface of liquid metal composed of gallium, iron, nickel and silicon, by catalytic activation of methane and diffusion of carbon atoms into and within the subsurface regions. We found that the supersaturation of carbon in the liquid metal subsurface leads to the nucleation and growth of diamonds, with Si playing an important part in stabilizing tetravalently bonded carbon clusters that play a part in nucleation. Growth of (metastable) diamond in liquid metal at moderate temperature and 1?atm pressure opens many possibilities for further basic science studies and for the scaling of this type of growth.