Highly tunable magnetic phases in transition metal dichalcogenide Fe$_{1/3+δ}$NbS$_2$
Shan Wu, Zhijun Xu, Shannon C. Haley, Sophie F. Weber, Arany Acharya, Eran Maniv, Yiming Qiu, A. A. Aczel, Jeffrey B. Neaton, James G. Analytis, Robert J. Birgeneau
Layered transition metal dichalcogenides (TMDCs) host a plethora of interesting physical phenomena ranging from charge order to superconductivity. By introducing magnetic ions into 2H-NbS$_2$, the material forms a family of magnetic intercalated TMDCs T$_x$NbS$_2$ (T = 3d transition metal). Recently, Fe$_{1/3+δ}$NbS$_2$ has been found to possess intriguing resistance switching and magnetic memory effects coupled to the Néel temperature of T$_N \sim 45$ K [1,2]. We present comprehensive single crystal neutron diffraction measurements on under-intercalated ($δ\sim -0.01$), stoichiometric, and over-intercalated ($δ\sim 0.01$) samples. Magnetic defects are usually considered to suppress magnetic correlations and, concomitantly, transition temperatures. Instead, we observe highly tunable magnetic long-ranged states as the Fe concentration is varied from under-intercalated to over-intercalated, that is from Fe vacancies to Fe interstitials. The under- and over- intercalated samples reveal distinct antiferromagnetic stripe and zig-zag orders, associated with wave vectors $k_1$ = (0.5, 0, 0) and $k_2$ = (0.25, 0.5, 0), respectively. The stoichiometric sample shows two successive magnetic phase transitions for these two wave vectors with an unusual rise-and-fall feature in the intensities connected to $k_1$. We ascribe this sensitive tunability to the competing next nearest neighbor exchange interactions and the oscillatory nature of the Ruderman-Kittel-Kasuya-Yosida (RKKY) mechanism. We discuss experimental observations that relate to the observed intriguing switching resistance behaviors. Our discovery of a magnetic defect tuning of the magnetic structure in bulk crystals Fe$_{1/3+δ}$NbS$_2$ provides a possible new avenue to implement controllable antiferromagnetic spintronic devices.
Tuning the Charge Transfer of Transition Metal Dichalcogenides via Misfit Layer Compounds
Institut des Nanosciences de Paris（巴黎纳米科学研究所）；Universität Würzburg（维尔茨堡大学）；Institut des Matériaux de Nantes Jean Rouxel（南特让·鲁克尔材料研究所）；University of Trento（特伦托大学）；Synchrotron SOLEIL（SOLEIL同步辐射中心）；Institut de Physique de Rennes（雷恩物理研究所）
Ising superconductivity in monolayer niobium dichalcogenide alloys
NbSe $_{2}$和NbS $_{2}$是同构的二维材料，当降低到单层极限时，它们表现出对比鲜明的超导性质。单层NbSe $_{2}$是一种Ising超导体，而单层NbS $_{2}$的超导性还没有报道。NbS $_{x}$ Se $_{2-x}$合金的超导转变温度与硫含量呈现出有趣的非单调关系，这被解释为分形超导电性的一种表现。然而，关于这一结果的几个关键问题是未知的：（1）合金的电子结构是否与母体化合物不同，（2）已被证明是突出的单层NbSe $_{2}$的自旋波动也存在于合金中？利用第一性原理计算，我们发现NbS $_{x}$ Se $_{2-x}$合金中费米能级的态密度和接近磁性的态密度都比母体化合物降低了，前者会降低相变温度，而后者会提高相变温度，我们还发现在NbSe $_{2}$中可能会形成大浓度的Se空位，这可能是磁对断裂缺陷.基于我们的结果，我们提出了NbSPDMATHABMN Se $_{2-x}$合金超导转变温度非单调行为的另一种解释，它不需要多重分形的猜想.
Tunability of the magnetic properties in Ni intercalated transition metal dichalcogenide NbSe$_2$
International Research Centre Magtop, Institute of Physics, Polish Academy of Sciences（波兰科学院物理研究所磁学国际研究中心）；Institute of Physics, Polish Academy of Sciences（波兰科学院物理研究所）
Stoichiometry-Controlled Structural Order and Tunable Antiferromagnetism in $\mathrm{Fe}_{x}\mathrm{NbSe_2}$ ($0.05 \le x \le 0.38$)
Tsung-Dao Lee Institute, School of Physics and Astronomy, Shanghai Jiao Tong University（上海交通大学物理与天文学院李政道研究所）；Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology（南方科技大学量子科学与工程研究院）；International Quantum Academy（国际量子科学院）；Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University（上海交通大学张江高等研究院）；State Key Laboratory of Micro-nano Engineering Science, Shanghai Jiao Tong University（上海交通大学微纳制造技术国家重点实验室）
Atomically-precise synthesis and simultaneous integration of 2D transition metal dichalcogenides enabled by nano-confinement
Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）；Suzhou Laboratory（苏州实验室）；Institute of Technology for Carbon Neutrality, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences（中国科学院深圳先进技术研究院碳中和技术研究所）；Frontier Institute of Science and Technology, Xi’an Jiaotong University（西安交通大学前沿科学中心）；Department of Engineering Mechanics and Center for Nano and Micro Mechanics, Tsinghua University（清华大学工程力学系微纳力学与微系统教育部重点实验室）；Faculty of Materials Science and Energy Engineering, Shenzhen University of Advanced Technology（深圳先进材料能源学院）
Ab initio prediction of strain-tunable spin defects in quasi-1D TiS3 and NbS3 nanowires
Virginia Tech National Security Institute（弗吉尼亚理工大学国家安全研究所）；Department of Materials Science and Engineering, Virginia Tech（弗吉尼亚理工学院材料科学与工程系）；Department of Physics, Virginia Tech（弗吉尼亚理工学院物理系）；Virginia Tech Center for Quantum Information Science and Engineering（弗吉尼亚理工大学量子信息科学与工程中心）
On the origin of diverse interlayer charge redistribution in transition-metal dichalcogenides
Key Laboratory of Optic-Electronic Information and Materials of Hebei Province, Hebei Research Center of the Basic Discipline for Computational Physics, College of Physics Science and Technology, Hebei University（河北省光电信息与材料重点实验室，计算物理基础学科河北研究中心，河北大学物理科学与工程学院）
Doping tunable charge density waves in misfit layer compounds
Institut des Nanosciences de Paris（巴黎纳米科学研究所）；Universität Würzburg（维尔茨堡大学）；Institut des Matériaux de Nantes Jean Rouxel（南特让·鲁克塞尔材料研究所）；University of Trento（特伦托大学）；Pavol Jozef Šafárik University（帕沃尔·约瑟夫·沙法里克大学）
Squeezed metallic droplet with tunable Kubo gap and charge injection in transition metal dichalcogenides
将大块金属的尺寸缩小到纳米级会导致电子能级的离散，即所谓的久保间隙。重整化的电子性质与一个可调的和尺寸依赖的Kubo间隙呈现迷人的光子发射和电子隧穿。与通常的三维（3D）金属簇相比，在这里我们证明了Kubo间隙可以用二维（2D）金属过渡金属二硫属化物（即，1 T ′-相MoTe 2）纳米团簇嵌入半导体多晶型物（即，1H相MoTe 2）。这种1 T ′-1H MoTe 2纳米畴类似于在2D空间中挤压的3D金属液滴，其显示出强的极化灾难，同时保持其键的完整性，这在传统的δ-间隙3D簇中是不存在的。宿主2D MoTe 2的弱屏蔽导致这种伪金属系统的光子发射和载流子在1 T '-1H-1T'同质结中的弹道注入，这可以在传感器和2D可重构器件中找到应用。
Machine learning model for efficient nonthermal tuning of the charge density wave in monolayer NbSe$_2$
Ruđer Bošković Institute（鲁德·博什科维奇研究所）；Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Università degli Studi di Modena e Reggio Emilia（摩德纳和雷焦艾米利亚大学物理、信息和数学科学系）；CNR NANO S3（意大利国家研究委员会纳米S3研究所）；Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford（牛津大学化学系无机化学实验室）；Centre for Advanced Laser Techniques, Institute of Physics, Zagreb（萨格勒布物理研究所先进激光技术研究中心）
Tunable structure-activity correlations of molybdenum dichalcogenides (MoX$_2$; X= S, Se, Te) electrocatalysts via hydrothermal methods: insight into optimizing the electrocatalytic performance for hydrogen generation
