《自然》20250703出版一周论文导读

 

编译|未玖

 Nature, 3 July 2025, Volume 643, Issue 8070 

《自然》2025年7月3日，第643卷，8070期 

天文学Astronomy   

Carbonate formation and fluctuating habitability on Mars 

火星上碳酸盐的形成和宜居性的波动    

▲ 作者：Edwin S. Kite, Benjamin M. Tutolo, Madison L. Turner, Heather B. Franz, David G. Burtt, Thomas F. Bristow, et al.

▲链接：

https://www.nature.com/articles/s41586-025-09161-1 

▲摘要：火星表面宜居性丧失的原因尚不明确，同位素数据表明存在碳酸盐的“缺失汇”。火星沉积岩（包括盖尔陨石坑内约4千米厚的地层）记录了表层和浅层地下液态水的古气候。这些水体是间歇性的，空间分布零散且不连贯，且在火星地质史后期一直持续存在。如果其沉积岩形成如地球般将二氧化碳封存为丰富的碳酸盐（最近在盖尔坑原位证实了这一点），那么这些特征便可合理解释。

研究表明，太阳光度、液态水和碳酸盐形成之间的负反馈可以解释火星零散绿洲的存在。在该模型中，太阳光度的增强促进了液态水的稳定性，从而形成碳酸盐，降低了大气二氧化碳的分压，反而限制了液态水。混沌轨道摄动调控干湿循环。该负反馈将液态水限制在绿洲中，使火星自调节为一个沙漠星球。研究将融雪建模为水源，但该反馈也可将地下水作为水源。模型输出表明，盖尔坑完整记录了表层和近表层环境中液态水稳定性的预期主要事件。最终，大气厚度接近水的三相点，削弱了液态水的持续稳定性，从而降低了地表环境中的宜居性。研究假设在盖尔坑发现的碳酸盐含量具有代表性，因此该观点属于可检验假说而非确凿证据。

▲ Abstract： The cause of Mars’s loss of surface habitability is unclear, with isotopic data suggesting a ‘missing sink’ of carbonate. Past climates with surface and shallow-subsurface liquid water are recorded by Mars’s sedimentary rocks, including strata in the approximately 4-km-thick record at Gale Crater. Those waters were intermittent, spatially patchy and discontinuous, and continued remarkably late in Mars’s history—attributes that can be understood if, as on Earth, sedimentary-rock formation sequestered carbon dioxide as abundant carbonate (recently confirmed in situ at Gale). Here we show that a negative feedback among solar luminosity, liquid water and carbonate formation can explain the existence of intermittent Martian oases. In our model, increasing solar luminosity promoted the stability of liquid water, which in turn formed carbonate, reduced the partial pressure of atmospheric carbon dioxide and limited liquid water. Chaotic orbital forcing modulated wet–dry cycles. The negative feedback restricted liquid water to oases and Mars self-regulated as a desert planet. We model snowmelt as the water source, but the feedback can also work with groundwater as the water source. Model output suggests that Gale faithfully records the expected primary episodes of liquid water stability in the surface and near-surface environment. Eventually, atmospheric thickness approaches water’s triple point, curtailing the sustained stability of liquid water and thus habitability in the surface environment. We assume that the carbonate content found at Gale is representative, and as a result we present a testable idea rather than definitive evidence.    

 物理学Physics   

Energy–speed relationship of quantum particles challenges Bohmian mechanics 

量子粒子的能量-速度关系挑战玻姆力学    

▲ 作者：Violetta Sharoglazova, Marius Puplauskis, Charlie Mattschas, Chris Toebes & Jan Klaers

▲链接：

https://www.nature.com/articles/s41586-025-09099-4 

▲摘要：经典力学将粒子动能（因其运动而保持的能量）描述为恒正值。相比之下，量子力学则用波函数描述粒子运动，其中可能出现局域负动能区域。当波函数振幅显著衰减时，就会发生这种现象，通常与量子隧穿效应有关。研究分析了两个耦合波导系统中粒子的量子力学运动，其中波导间的粒子数转移充当计时器，从而确定了粒子沿波导轴的速度。通过将该方案应用于反射势垒的指数衰减量子态，研究确定了具有局域负动能粒子的能量-速度关系。研究发现粒子的能量越低（即局域动能越负），势垒内测量的速度就越高。

该发现为正在进行的隧穿时间争议提供了新见解，可被视为对量子力学中玻姆轨迹的测试。对于后者，研究组发现所测的能量-速度关系与玻姆力学中引导方程所假设的粒子动力学不一致。

▲ Abstract： Classical mechanics characterizes the kinetic energy of a particle, the energy it holds due to its motion, as consistently positive. By contrast, quantum mechanics describes the motion of particles using wave functions, in which regions of negative local kinetic energy can emerge. This phenomenon occurs when the amplitude of the wave function experiences notable decay, typically associated with quantum tunnelling. Here, we investigate the quantum mechanical motion of particles in a system of two coupled waveguides, in which the population transfer between the waveguides acts as a clock, allowing particle speeds along the waveguide axis to be determined. By applying this scheme to exponentially decaying quantum states at a reflective potential step, we determine an energy–speed relationship for particles with negative local kinetic energy. We find that the smaller the energy of the particles—in other words, the more negative the local kinetic energy—the higher the measured speed inside the potential step. Our findings contribute to the ongoing tunnelling time debate and can be viewed as a test of Bohmian trajectories in quantum mechanics. Regarding the latter, we find that the measured energy–speed relationship does not align with the particle dynamics postulated by the guiding equation in Bohmian mechanics.    

 材料科学Materials Science   

Efficient near-infrared harvesting in perovskite–organic tandem solar cells

 钙钛矿-有机叠层太阳能电池中的高效近红外采集    

 ▲ 作者：Zhenrong Jia, Xiao Guo, Xinxing Yin, Ming Sun, Jiawei Qiao, Xinyu Jiang, et al.

▲链接：

 https://www.nature.com/articles/s41586-025-09181-x 

▲摘要：钙钛矿和有机半导体的宽带隙可调性使钙钛矿-有机叠层太阳能电池的开发具有很高的理论效率。然而，已报道的钙钛矿-有机叠层太阳能电池的认证效率仍低于单结钙钛矿太阳能电池，主要是因为窄带隙有机子电池中的近红外光生电流不足。

 研究设计并合成了一种不对称的非富勒烯受体（NFA）P2EH-1V，其特征是单侧共轭π桥，可在保持理想激子解离和纳米形貌的同时将光学带隙降低到1.27?eV。瞬态吸收光谱证实了从P2EH-1V向给体PM6的有效空穴转移。基于P2EH-1V的器件在保持电荷产生效率的情况下，将非辐射电压损失降低了0.20?eV。   研究实现了17.9%的有机底部电池效率，短路电流密度（Jsc）高达28.60 mA cm