天文学Astronomy

▲ 作者：Noel D. Richardson, Clarissa M. Pavao, Jan J. Eldridge, Herbert Pablo, André-Nicolas Chené, Peter Wysocki, Douglas R. Gies, George Younes & Jeremy Hare

▲ 链接：

https://www.nature.com/articles/s41586-022-05618-9

▲ 摘要：

在此，我们展示了最近发现的高质量x射线双星CPD −29 2176 (CD −29 5159; SGR 0755-2933)所具有的演化历史表明，中子星成分是在极度剥离超新星时期形成的。此双星的轨道元素在周期和离心率上都与已知轨道周期和离心率的14个Be x射线双星中的1个相似。

对极度剥离超新星的前身星系统的识别是必要的，因为它们的演化路径导致了双中子星系统的形成。双中子星，如被观测到有电磁和引力能、能产生千新星GW170817的系统，已知会产生大量的重元素。

▲ Abstract：

Here we show that a recently discovered high-mass X-ray binary, CPD −29 2176 (CD −29 5159; SGR 0755-2933), has an evolutionary history that shows the neutron star component formed during an ultra-stripped supernova. The binary has orbital elements that are similar both in period and in eccentricity to 1 of 14 Be X-ray binaries that have known orbital periods and eccentricities. The identification of the progenitors systems for ultra-stripped supernovae is necessary as their evolution pathways lead to the formation of binary neutron star systems. Binary neutron stars, such as the system that produced the kilonova GW170817 that was observed with both electromagnetic and gravitational energy, are known to produce a large quantity of heavy elements.

物理学Physics

▲ 作者：Xing-Yan Chen, Andreas Schindewolf, Sebastian Eppelt, Roman Bause, Marcel Duda, Shrestha Biswas, Tijs Karman, Timon Hilker, Immanuel Bloch & Xin-Yu Luo

▲ 链接：

https://www.nature.com/articles/s41586-022-05651-8

▲ 摘要：

在此，我们展示了一种适用于广泛范围的新型极性分子。所谓的场联共振发生在微波修饰的分子散射中，因为分子间势中存在稳定的宏观四聚体状态。

我们确定了超冷基态钠-钾分子之间的两种共振，并使用微波频率和极化将非弹性碰撞率调整为3个数量级，从酉极限到远低于普遍状态。

场联共振提供了一个调谐旋钮来独立控制弹性接触相互作用和偶极子-偶极子相互作用，同时观察到热化速率的修正。我们的实验结果为超冷极性分子之间的共振散射提供了普适的策略，为实现偶极超流体和分子超固体以及组装超冷多原子分子铺平了道路。

▲ Abstract：

Here we demonstrate a new type of scattering resonance that is universal for a wide range of polar molecules. The so-called field-linked resonances occur in the scattering of microwave-dressed molecules because of stable macroscopic tetramer states in the intermolecular potential. We identify two resonances between ultracold ground-state sodium–potassium molecules and use the microwave frequencies and polarizations to tune the inelastic collision rate by three orders of magnitude, from the unitary limit to well below the universal regime. The field-linked resonance provides a tuning knob to independently control the elastic contact interaction and the dipole–dipole interaction, which we observe as a modification in the thermalization rate. Our result provides a general strategy for resonant scattering between ultracold polar molecules, which paves the way for realizing dipolar superfluids and molecular supersolids, as well as assembling ultracold polyatomic molecules.

▲ 作者：Lysander Christakis, Jason S. Rosenberg, Ravin Raj, Sungjae Chi, Alan Morningstar, David A. Huse, Zoe Z. Yan & Waseem S. Bakr

▲ 链接：

https://www.nature.com/articles/s41586-022-05558-4

▲ 摘要：

在此，我们使用量子气相显微镜来测量限制在二维光学晶格中的极性钠铷分子的量子相关性的位置分辨动力学。

通过利用分子的2个旋转状态，我们实现了粒子之间具有偶极相互作用的自旋1/2系统，产生了量子自旋交换模型。我们研究了空间各向同性和各向异性相互作用的非平衡自旋系统热化过程中相关关系的演化。

此外，我们利用周期微波脉冲研究了自旋各向异性海森堡模型的相关动力学。这些实验推动了探测和控制超冷分子相互作用系统的研究前沿，具备探索量子物质新体系和描述量子计算和计量学中有用的纠缠态的前景。

▲ Abstract：

Here we use quantum gas microscopy to measure the site-resolved dynamics of quantum correlations of polar 23Na87Rb molecules confined in a two-dimensional optical lattice. By using two rotational states of the molecules, we realize a spin-1/2 system with dipolar interactions between particles, producing a quantum spin-exchange model. We study the evolution of correlations during the thermalization process of an out-of-equilibrium spin system for both spatially isotropic and anisotropic interactions. Furthermore, we examine the correlation dynamics of a spin-anisotropic Heisenberg model engineered from the native spin-exchange model by using periodic microwave pulses. These experiments push the frontier of probing and controlling interacting systems of ultracold molecules, with prospects for exploring new regimes of quantum matter and characterizing entangled states that are useful for quantum computation and metrology.

▲ 作者：Juliana J. Park, Yu-Kun Lu, Alan O. Jamison, Timur V. Tscherbul & Wolfgang Ketterle

▲ 链接：

https://www.nature.com/articles/s41586-022-05635-8

▲ 摘要：

在此，我们报告一个在2个三重态基态钠锂分子碰撞中的非常明显且狭窄（25 mG）的费希巴赫共振。

这种分子费希巴赫共振有两个特殊的特征。第一，由于化学反应性强，碰撞损失率比背景损失率提高了两个数量级以上，背景损失率在p波普遍值处饱和。第二，共振位于两个开放通道几乎退化的磁场中。这意味着中间复合体主要衰变到第二开放通道。

我们使用类似于法布里-珀罗谐振腔的耦合模式模型来描述谐振损耗特征。我们的观察为即使在没有反应障碍的系统中也存在长时间相干的中间配合物提供了有力证据，并为化学反应的相干控制带来了可能性。

▲ Abstract：

Here we report a very pronounced and narrow (25 mG) Feshbach resonance in collisions between two triplet ground-state NaLi molecules. This molecular Feshbach resonance has two special characteristics. First, the collisional loss rate is enhanced by more than two orders of magnitude above the background loss rate, which is saturated at the p-wave universal value, owing to strong chemical reactivity. Second, the resonance is located at a magnetic field where two open channels become nearly degenerate. This implies that the intermediate complex predominantly decays to the second open channel. We describe the resonant loss feature using a model with coupled modes that is analogous to a Fabry–Pérot cavity. Our observations provide strong evidence for the existence of long-lived coherent intermediate complexes even in systems without reaction barriers and open up the possibility of coherent control of chemical reactions.

材料科学Materials Science

▲ 作者：Jiho Shin, Hyunseok Kim, Suresh Sundaram et al.

▲ 链接：

https://www.nature.com/articles/s41586-022-05612-1

▲ 摘要：

在此，我们报告了已知范围内最高阵列密度（5100像素/英寸）和最小尺寸（4微米）的全彩色垂直堆叠µLEDs。这是通过基于二维材料的层转移技术实现的，该技术允许在二维材料涂层基片上通过远程外延或范德华外延、机械释放和堆叠LED等工序来生长近亚微米厚度的RGB LEDs。

有史以来最小的、约9微米的堆叠高度是制造高阵列密度LED的关键因素。我们还演示了蓝色µLEDs与硅膜晶体管的垂直集成，可用于有源矩阵应用。这些研究结果为制造用于增强现实和虚拟现实的全彩Micro LED显示器奠定了基础，同时也为更广泛的三维集成设备类别提供了通用平台。

▲ Abstract：

Here we report full-colour, vertically stacked µLEDs that achieve, to our knowledge, the highest array density (5,100 pixels per inch) and the smallest size (4 µm) reported to date. This is enabled by a two-dimensional materials-based layer transfer technique that allows the growth of RGB LEDs of near-submicron thickness on two-dimensional material-coated substrates via remote or van der Waals epitaxy, mechanical release and stacking of LEDs, followed by top-down fabrication. The smallest-ever stack height of around 9 µm is the key enabler for record high µLED array density. We also demonstrate vertical integration of blue µLEDs with silicon membrane transistors for active matrix operation. These results establish routes to creating full-colour µLED displays for augmented and virtual reality, while also offering a generalizable platform for broader classes of three-dimensional integrated devices.

▲ 作者：Ki Seok Kim, Doyoon Lee, Celesta S. Chang, Seunghwan Seo, Yaoqiao Hu et al.

▲ 链接：

https://www.nature.com/articles/s41586-022-05524-0

▲ 摘要：

在此，我们介绍了一种确定性的限域生长技术，可以同时解决三个问题，从而在任意衬底上获得晶圆规模的单畴2D单层阵列及其异质结。我们通过在两英寸衬底上的SiO₂掩膜图案定义一个选择性生长区域，从几何上限制了第一组晶核的生长。

由于在微米级SiO₂沟槽上的生长时间大大缩短，我们在引入第二组晶核之前，通过第一组晶核的短时间生长来填充沟槽，从而无需外延晶种，在任意基底上获得了晶圆规模的单畴单层WSe₂阵列。

用同样的原理进一步生长过渡金属二卤族化合物，形成单畴MoS₂/WSe₂异质结。我们的成果将为二维材料适应工业环境奠定坚实基础。

▲ Abstract：

Here we introduce a deterministic, confined-growth technique that can tackle these three issues simultaneously, thus obtaining wafer-scale single-domain 2D monolayer arrays and their heterostructures on arbitrary substrates. We geometrically confine the growth of the first set of nuclei by defining a selective growth area via patterning SiO₂ masks on two-inch substrates. Owing to substantial reduction of the growth duration at the micrometre-scale SiO₂ trenches, we obtain wafer-scale single-domain monolayer WSe₂ arrays on the arbitrary substrates by filling the trenches via short growth of the first set of nuclei, before the second set of nuclei is introduced, thus without requiring epitaxial seeding. Further growth of transition metal dichalcogenides with the same principle yields the formation of single-domain MoS₂/WSe₂ heterostructures. Our achievement will lay a strong foundation for 2D materials to fit into industrial settings.