Deping Guo*, Weihan Zhang, Canbo Zong, Cong Wang, Wei Ji
Abstract:
Luttinger compensated antiferromagnets (LcAFMs), combining spin polarization with vanishing net magnetization, offering distinct advantages for next-generation spintronic applications. Using first-principles calculations, we demonstrate that conventional antiferromagnetic CrCl2 double chains can be transformed into one-dimensional LcAFMs under an external electric field, exhibiting pronounced isotropic spin splitting. The magnitude of the splitting, as well as the band gap, can be effectively tuned by both in-plane and out-of-plane fields, thereby providing greater controllability than in two-dimensional counterparts. To further enhance the tunability, we design a nearly lattice-matched CrCl2/MoTe2 heterostructure and uncover that interfacial charge transfer generates a built-in electric field, inducing spin splitting comparable to that driven by external fields. These results establish interfacial engineering as a highly efficient route to realize and manipulate LcAFM states in low-dimensional magnets, expanding the design principles for spintronic functionalities at the nanoscale.
Kuakua Lu#, Yun Li#,*, Qijing Wang#,* Linlu Wu#, Xinglong Ren, Xu Chen, Luhao Liu, Yating Li, Xiaoming Xu, Qingkai Zhang, Di Wang, Liqi Zhou, Mingfei Xiao, Sai Jiang, Mengjiao Pei, Haoxin Gong, William Wood, Ian E. Jacobs, Junzhan Wang, Gang Chen, Peng Wang, Zhaosheng Li, Chunfeng Zhang, Xinran Wang, Xu Wu, Yeliang Wang, Wei Ji, Songlin Li, Jingsi Qiao*, Yi Shi*, Henning Sirringhaus*
Abstract:
Metallic charge transport of field-induced carriers can be observed in single-crystal silicon over a wide temperature range. Such behaviour is rare in undoped organic semiconductors but is beneficial for engineering devices with advanced performance. Here we report metallic charge transport in conjugated molecular bilayers down to 8 K with an electrical conductivity of up to 245 S cm−1 and a Hall mobility larger than 100 cm2 V−1 s−1 at 20 K. We use molecular-crystal bilayers of the organic semiconductor 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene. We infer that this transport behaviour originates from the phenyl bridge coupling between the two molecular layers, which suppresses molecular vibrations and weakens Coulomb interactions. We develop a controlled method for introducing defects, using which we observe a disorder-driven metal–insulator transition in the molecular crystal.
The integration of electronic and photonic chips hinges on the availability of efficient light sources and modulators that are compatible with on-chip interconnects. Among these, mid-infrared (mid-IR) emitters are especially critical, as they enable low-loss transmission through atmospheric windows and unlock powerful capabilities for molecular fingerprinting and chemical sensing. In this study, we demonstrate that 2D tellurium (Te) nanoflakes can serve as highly efficient, electrically tunable, and linearly polarized mid-IR emitters. Leveraging the narrow direct bandgap (≈0.36 eV) and anisotropic crystal symmetry of Te nanoflakes, we achieve electrically tunable mid-IR photoluminescence (PL) with near-complete PL intensity modulation, a stable emission wavelength (≈3.4 µm), and near-perfect linear polarization. In addition, we demonstrate a dual-gate device that allows independent control of the electrostatic doping and vertical electric field, and further theoretical analysis reveals that the electrical tunability of the PL intensity originates primarily from the gate-controlled carrier density. Building on this robust control, we demonstrate high-speed electro-optical switches and programmable logic gates for on-chip encryption, underscoring the excellent compatibility of Te with advanced optoelectronic circuits. Collectively, these advances establish Te as a cornerstone material for hybrid electronic-photonic systems, directly addressing the urgent demand for mid-IR components in next-generation optical interconnects.
Li Huang, Yuqing Xing, Qi Zheng, Senhao Lv, Lan Chen, Hui Chen, Haitao Yang, Wei Ji and Hong-Jun Gao*
Abstract:
Altermagnetic materials, with real-space antiferromagnetic arrangement and reciprocal-space anisotropic spin splitting, have attracted much attention. However, the spin splitting is small in most altermagnetic materials, which is a disadvantage to their application in electronic devices. In this study, based on symmetry analysis and the first-principles electronic structure calculations, we predict for the first time two Luttinger compensated bipolarized magnetic semiconductors Mn(CN)2 and Co(CN)2 with isotropic spin splitting as in the ferromagnetic materials. Our further analysis shows that the Luttinger compensated magnetism here depends not only on spin group symmetry, but also on the crystal field splitting and the number of d-orbital electrons. In addition, the polarized charge density indicates that both Mn(CN)2 and Co(CN)2 have the quasi-symmetry T{tau} , resulting from the crystal field splitting and the number of d-orbital electrons. The Luttinger compensated magnetism not only has the zero total magnetic moment as the antiferromagnetism, but also has the isotropic spin splitting as the ferromagnetism, thus our work not only provides theoretical guidance for searching Luttinger compensated magnetic materials with distinctive properties, but also provides a material basis for the application in spintronic devices.
Altermagnetic materials, with real-space antiferromagnetic arrangement and reciprocal-space anisotropic spin splitting, have attracted much attention. However, the spin splitting is small in most altermagnetic materials, which is a disadvantage to their application in electronic devices. In this study, based on symmetry analysis and the first-principles electronic structure calculations, we predict for the first time two Luttinger compensated bipolarized magnetic semiconductors Mn(CN)2 and Co(CN)2 with isotropic spin splitting as in the ferromagnetic materials. Our further analysis shows that the Luttinger compensated magnetism here depends not only on spin group symmetry, but also on the crystal field splitting and the number of d-orbital electrons. In addition, the polarized charge density indicates that both Mn(CN)2 and Co(CN)2 have the quasi-symmetry T{\tau} , resulting from the crystal field splitting and the number of d-orbital electrons. The Luttinger compensated magnetism not only has the zero total magnetic moment as the antiferromagnetism, but also has the isotropic spin splitting as the ferromagnetism, thus our work not only provides theoretical guidance for searching Luttinger compensated magnetic materials with distinctive properties, but also provides a material basis for the application in spintronic devices.
