Nature Communications
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2024
·Vol. 15
·期 1
·1-7
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IF 14.7
Xing Dong,Tong Bingbing,Pan Senyang,Wang Zezhi,Luo Jianlin,Zhang Jinglei,Zhang Cheng-Long
Topological flat bands — where the kinetic energy of electrons is quenched — provide a platform for investigating the topological properties of correlated systems. Here, we report the observation of a topological flat band formed by polar-distortion-assisted Rashba splitting in the three-dimensional Dirac material ZrTe 5 . The polar distortion and resulting Rashba splitting on the band are directly detected by torque magnetometry and the anomalous Hall effect, respectively. The local symmetry breaking further flattens the band, on which we observe resistance oscillations beyond the quantum limit. These oscillations follow the temperature dependence of the Lifshitz–Kosevich formula but are evenly distributed in B instead of 1/B at high magnetic fields. Furthermore, the cyclotron mass gets anomalously enhanced about 10 2 times at fields ~ 20 T. Our results provide an intrinsic platform without invoking moiré or order-stacking engineering, which opens the door for studying topologically correlated phenomena beyond two dimensions.
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
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2020
·
IF 2.029
Chi Zhang,Jing Hui Zeng,Ye Feng Wang
Manganese doped titanium dioxide was synthesized using hydrothermal technique and applied to photo-anode films for quantum dot sensitized solar cells after combined with commercially available titania. The products and cells were characterized with XRD, TEM, and electrochemical methods. At the optimum Mn-doped TiO 2 content, an open circuit voltage of 0.61 V is received on CdS sensitized quantum dot solar cells with an overall efficiency of 2.9%. Mott-Schottky traces suggest that a more negative flat-band potential accounts for the higher voltage.
研究领域:
材料科学
·
光电化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2022
·
IF 8.025
Jing Hu,Zhenjun Xiong,Yuqing Liu,Jinyou Lin
Conventional petroleum-based synthetic polymeric fiber filter materials for separation may cause secondary pollution to the environment due to their non-degradable properties. Herein, we report a facile method of preparation of a biodegradable composite filter that can achieve filtration for air by underlaying the commercialized cellulose paper towel under electrospun zein fibers. The morphology of zein fibers was successfully steered via varying the weight ratios of ethanol/deionized water mixture solvent, as a result, the round or flat ribbon fibers were obtained. The effect of zein fiber morphology on air filtration performance was investigated both experimentally and theoretically. It was found that the flat ribbon fiber filter had a higher filtration efficiency (99%) for PM0.3 removal and a lower pressure drop (109 Pa) compared with the round zein fiber filter. Notably, the as-prepared composite filter can be biodegradable easily, contributing to green ecological environment. This work shows an efficient way to develop biodegradable filtration materials with the cheap price, easy availability of component materials, exhibiting a great potential application in air filtration area.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Photonics
·
2025
·
IF 6.7
Yanshu Shi,Jianhua Zhu,Xuekun Wang,Yiqian Wang,Qinghao Song,Lei Chen,Yumin Song,Wei Wu,Tingting Guo
Topological Photonics, exploring the topologically nontrivial states in photonics, is a fast-progressing research topic. Topological flat bands, fascinating features in topological photonics, have attracted much attention recently. Metal-phthalocyanine (MPc) molecular semiconductors are formed by molecular chains, offering a great platform to study topological states in low dimension. Previous work shows that the MPc molecular chain could be used to realize one-dimensional topological excitons based on the two-level systems. Therein, the topological flat band is a key feature in this type of topological excitons. Here, we have synthesized tin-phthalocyanine (SnPc) nanosheets. The ultraviolet–visible (UV–vis) and photoelectric experiments on these SnPc nanosheets are performed to characterize the one-dimensional topological flat bands. We demonstrate the strong evidence that the two photocurrent peaks at the wavelengths of 455 and 850 nm could originate from the topological flat bands within the B- and Q-spectral regions, respectively, according to our excitonic model. In addition, the photocurrent is improved by up to two orders using the nanosheets compared to the raw materials. Moreover, the previous excitonic model consisting of two-level systems is further generalized to incorporate both the B- and Q-bands by using three-level systems, interpreting the UV–vis spectra and the photocurrent peaks properly. The combination of our experimental and theoretical research shows that the stable and high broadband photoelectric performance of the SnPc nanosheets not only provides a new material platform for the organic photodetectors but also opens up a new research avenue for the observation of the topological flat band using molecular materials.
研究领域:
拓扑光子学
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凝聚态物理
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材料科学
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光电子学
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分子半导体
✓ 已验证
DOI
高影响因子
NATURE
·
2024
·Vol. 632
·期 8027
·1032-1037
·
IF 50.5
Liu Yi,Liu Zi-Yi,Bao Jin-Ke,Yang Peng-Tao,Ji Liang-Wen,Wu Si-Qi,Shen Qin-Xin,Luo Jun,Yang Jie,Liu Ji-Yong,Xu Chen-Chao,Yang Wu-Zhang,Chai Wan-Li,Lu Jia-Yi,Liu Chang-Chao,Wang Bo-Sen,Jiang Hao,Tao Qian,Ren Zhi,Xu Xiao-Feng,Cao Chao,Xu Zhu-An,Zhou Rui,Cheng Jin-Guang,Cao Guang-Han
Superconductivity in a highly correlated kagome system has been theoretically proposed for years (refs. 1 , 2 , 3 , 4 , 5 ), yet the experimental realization is hard to achieve 6 , 7 . The recently discovered vanadium-based kagome materials 8 , which exhibit both superconductivity 9 , 10 , 11 and charge-density-wave orders 12 , 13 , 14 , are nonmagnetic 8 , 9 and weakly correlated 15 , 16 . Thus these materials are unlikely to host the exotic superconductivity theoretically proposed. Here we report the discovery of a chromium-based kagome metal, CsCr 3 Sb 5 , which is contrastingly featured with strong electron correlations, frustrated magnetism and characteristic flat bands close to the Fermi level. Under ambient pressure, this kagome metal undergoes a concurrent structural and magnetic phase transition at 55 K, with a stripe-like 4 a 0 structural modulation. At high pressure, the phase transition evolves into two transitions, possibly associated with charge-density-wave and antiferromagnetic spin-density-wave orderings. These density-wave-like orders are gradually suppressed with pressure and, remarkably, a superconducting dome emerges at 3.65–8.0 GPa. The maximum of the superconducting transition temperature, T c max = 6.4 K, appears when the density-wave-like orders are completely suppressed at 4.2 GPa, and the normal state exhibits a non-Fermi-liquid behaviour, reminiscent of unconventional superconductivity and quantum criticality in iron-based superconductors 17 , 18 . Our work offers an unprecedented platform for investigating superconductivity in correlated kagome systems.
研究领域:
凝聚态物理
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强关联电子系统
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超导物理
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量子材料
✓ 已验证
DOI
高影响因子
ACS Nano
·
2025
·
IF 16
Yanyan Geng,Haoyu Dong,Renhong Wang,Jianfeng Guo,Shuo Mi,Le Lei,Yan Li,Li Huang,Fei Pang,Rui Xu,Weiqiang Yu,Hong-Jun Gao,Wei Ji,Weichang Zhou,Zhihai Cheng
The delicate interplay among the complex intra/inter-layer electron–electron and electron–lattice interactions is the fundamental prerequisite of these exotic quantum states, such as superconductivity, nematic order, and checkerboard charge order. Here, we explore the filling-dependent multiple stable intertwined electronic and atomic orders of the flat-band state of 1T-TaS2 encompassing hole order, phase orders, coexisting left- and right-chiral orders, and mixed phase/chiral orders via scanning tunneling microscopy (STM). Combining first-principles calculations, the emergent electronic/atomic orders can be attributed to the weakening of electron–electron correlations and stacking-dependent interlayer interactions. Moreover, achiral intermediate ring-like clusters and nematic charge density wave (CDW) states are successfully realized in intralayer chiral domain wall and interlayer heterochiral stacking regions through chiral overlap configurations. Our study not only deepens the understanding of filling-dependent electronic/atomic orders in flat-band systems but also offers perspectives for exploring exotic quantum states in correlated electronic systems.
研究领域:
凝聚态物理
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强关联电子系统
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量子材料
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表面科学
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电子结构理论
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）