Materials
·
2022
·Vol. 15
·期 20
·7372
·
IF 3.748
Xiaoxiao Zhang,Jun Hou,Wei Xia,Zhian Xu,Pengtao Yang,Anqi Wang,Ziyi Liu,Jie Shen,Hua Zhang,Xiaoli Dong,Yoshiya Uwatoko,Jianping Sun,Bosen Wang,Yanfeng Guo,Jinguang Cheng
RV6Sn6(R= Sc, Y, or rare earth) is a new family of kagome metals that have a similar vanadium structural motif asAV3Sb5(A= K, Rb, Cs) compounds. UnlikeAV3Sb5, ScV6Sn6is the only compound among the series ofRV6Sn6that displays a charge density wave (CDW) order at ambient pressure, yet it shows no superconductivity (SC) at low temperatures. Here, we perform a high-pressure transport study on the ScV6Sn6single crystal to track the evolutions of the CDW transition and to explore possible SC. In contrast toAV3Sb5compounds, the CDW order of ScV6Sn6can be suppressed completely by a pressure of about 2.4 GPa, but no SC is detected down to 40 mK at 2.35 GPa and 1.5 K up to 11 GPa. Moreover, we observed that the resistivity anomaly around the CDW transition undergoes an obvious change at ~2.04 GPa before it vanishes completely. The present work highlights a distinct relationship between CDW and SC in ScV6Sn6in comparison with the well-studiedAV3Sb5.Keywords:ScV6Sn6;charge density wave;high pressure
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Communications Materials
·
2025
·Vol. 6
·期 1
·1-9
·
IF 9.6
Luo Tao,Li Shen-Ao,Chen Liu-Cheng,Zhong Guo-Hua,Lin Hai-Qing,Chen Xiao-Jia
The hydrides based on transition metal nitrides are believed to be potential candidates of low-pressure superconductors. However, the relevant theoretical and experimental studies are lack. Here, we report a theoretical and experimental study of the superconductivity in Zr-N-H system. Two high-pressure phases of P 6 3 / m m c -ZrNH 2 and \(F\bar{4}3m\) -ZrNH are found to be stable. The superconducting transition temperature of the former is theoretically predicted to be relatively low with the values of 15–17 K, while the transition temperature of the latter is higher, close to 40 K at megabar pressures. The difference in transition temperature values mainly comes from the different forms of H in hydrides. To examine this theoretical prediction, we synthesize Zr-N-H ternary hydrides experimentally at high pressures by laser heating. The resistance measurements confirm the superconductivity of P 6 3 / m m c -ZrNH 2 and \(F\bar{4}3m\) -ZrNH. The present results provide a promising avenue for exploring the superconductivity in transition-metal nitrides.
研究领域:
材料科学
·
凝聚态物理
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2025
·
IF 6.4
Lijia Zhou,Xiangjiang Dong,Qiang Li,Xianran Xing
We systematically investigated the superconducting properties of 2H-PtxTaS2 (0 ≤ x ≤ 0.08). As the platinum (Pt) content increases, the charge density wave (CDW) in 2H-TaS2, which appears at approximately 75 K, is progressively suppressed and completely disappears in Pt0.06TaS2. Meanwhile, the superconducting transition temperature (Tc) first increases and then decreases, reaching its maximum value of approximately 4.85 K at x = 0.06. This phenomenon suggests a competitive interplay between CDW and superconductivity (SC) in this system. Further measurements of the superconducting parameters of Pt0.06TaS2 indicate that the enhancement of Tc is primarily attributed to an increase in the density of states at the Fermi level.
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Ruihong Li,Guangtao Liu,Qiang Jing,Xianyu Wang,Hongbo Wang,Jian Zhang,Yanmei Ma
The materials with topological phases have been a flexible platform for the realization of novel types of quantum matter due to their unique topology protected electron states. Herein, we report a comprehensive structural and electrical transport investigations on a topological insulator, SnBi 2 Te 4 , under high pressures by using diamond anvil cell techniques. Through in situ high pressure synchrotron x-ray diffraction studies, two structural phase transformations have been revealed. The powdered samples of SnBi 2 Te 4 transform from the initial layered quasi-two-dimensional structure (phase I) to a monoclinic C2/m structure (phase II) at about 7.14 GPa, and eventually develop into a site-disordered body centered cubic structure (phase III) at pressures above 18.9 GPa. Modifications of the electronic band structure have been discovered by the in situ high-pressure electrical measurements at low temperatures. It is noteworthy that three distinct pressure induced superconducting states have been observed, one in phase II and two in phase III. In each of the pressure induced superconducting states, the critical temperature Tc decreases with pressure. The maximum value of Tc is obtained in the third superconducting state emerging at the highest pressure range, which is 8.9 K at 22.3 GPa. A deep understanding of the relationship between the pressure induced structure-dependent superconducting states and the ambient-pressure topologically insulating state of SnBi 2 Te 4 may shed light on the universal physical nature that creates topologically insulating or superconducting states.
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2023
·
IF 10.9
Mingxin Zhang,Cuiying Pei,Qi Wang,Yi Zhao,Changhua Li,Weizheng Cao,Shihao Zhu,Juefei Wu,Yanpeng Qi
Recently, the discovery of superconductivity with a critical temperature T c up to 80 K in Ruddlesden–Popper phases La n +1 Ni n O 3 n +1 ( n = 2) under pressure has garnered considerable attention. Up to now, the superconductivity was only observed in La 3 Ni 2 O 7 single crystal grown with the optical-image floating zone furnace under oxygen pressure. It remains to be understood the effect of chemical doping on superconducting La 3 Ni 2 O 7 as well as other Ruddlesden–Popper phases. Here, we systematically investigate the effect of external pressure and chemical doping on polycrystalline Ruddlesden–Popper phases. Our results demonstrate that the application of pressure and doping effectively tunes the transport properties of Ruddlesden–Popper phases. We find pressure-induced superconductivity up to 86 K in La 3 Ni 2 O 7 polycrystalline sample, while no signatures of superconductivity are observed in La 2 NiO 4 and La 4 Ni 3 O 10 polycrystalline samples under high pressure up to 50 GPa. Our study sheds light on the exploration of high- T c superconductivity in nickelates.
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2016
·Vol. 7
·期 1
·1-8
·
IF 11.329
Zhu Xiaojiao,Guo Yuqiao,Cheng Hao,Dai Jun,An Xingda,Zhao Jiyin,Tian Kangzhen,Wei Shiqiang,Cheng Zeng Xiao,Wu Changzheng,Xie Yi
Ferromagnetism is usually deemed incompatible with superconductivity. Consequently, the coexistence of superconductivity and ferromagnetism is usually observed only in elegantly designed multi-ingredient structures in which the two competing electronic states originate from separate structural components. Here we report the use of surface molecular adsorption to induce ferromagnetism in two-dimensional superconducting NbSe 2 , representing the freestanding case of the coexistence of superconductivity and ferromagnetism in one two-dimensional nanomaterial. Surface-structural modulation of the ultrathin superconducting NbSe 2 by polar reductive hydrazine molecules triggers a slight elongation of the covalent Nb–Se bond, which weakens the covalent interaction and enhances the ionicity of the tetravalent Nb with unpaired electrons, yielding ferromagnetic ordering. The induced ferromagnetic momentum couples with conduction electrons generating unique correlated effects of intrinsic negative magnetoresistance and the Kondo effect. We anticipate that the surface molecular adsorption will be a powerful tool to regulate spin ordering in the two-dimensional paradigm.
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Kuan Li,Weijie Lin,Ruixin Guo,Shu Guo,Lingyong Zeng,Longfu Li,Peifeng Yu,Kangwang Wang,Chao Zhang,Huixia Luo
Medium- and high-entropy alloy (MEA and HEA) superconductors have attracted considerable interest since their discovery. This paper reports the superconducting properties of ternary tungsten-containing MEA V 4 Ti 2 W for the first time. V 4 Ti 2 W is a type II superconductor with a body-centered cubic (BCC) structure. This structure belongs to the space group Im 3 ̅ m (No. 229) with the cell parameters a = b = c = 3.10673(14) Å. Experimental results of resistivity, magnetization, and heat capacity indicate that the superconducting transition temperature of the MEA V 4 Ti 2 W is roughly 5.0 K. The critical magnetic fields at the upper and lower ends are 9.93(2) T and 40.7(3) mT, respectively. Interestingly, few BCC MEA superconductors with VEC greater than 4.8 have been found. The addition of tungsten leads to a VEC of 4.83 e/a for V 4 Ti 2 W, which is rarely higher than the 4.8 value. Adding tungsten element expands the variety of MEA alloys, which may improve the microstructure and mechanical properties of materials and even superconducting properties. This material could potentially offer a new platform for the investigation of innovative MEA and HEA superconductors.
研究领域:
材料科学
·
凝聚态物理
✓ 已验证
DOI
高影响因子
NATURE MATERIALS
·
2014
·Vol. 14
·期 3
·325-329
·
IF 36.425
Lu X. F.,Wang N. Z.,Wu H.,Wu Y. P.,Zhao D.,Zeng X. Z.,Luo X. G.,Wu T.,Bao W.,Zhang G. H.,Huang F. Q.,Huang Q. Z.,Chen X. H.
Iron selenide superconductors exhibit a number of unique characteristics that are helpful for understanding the mechanism of superconductivity in high- T c iron-based superconductors more generally. However, in the case of A x Fe 2 Se 2 (A = K, Rb, Cs), the presence of an intergrown antiferromagnetic insulating phase makes the study of the underlying physics problematic. Moreover, FeSe-based systems intercalated with alkali metal ions, NH 3 molecules or organic molecules are extremely sensitive to air, which prevents the further investigation of their physical properties. It is therefore desirable to find a stable and easily accessible FeSe-based superconductor to study its physical properties in detail. Here, we report the synthesis of an air-stable material, (Li 0.8 Fe 0.2 )OHFeSe, which remains superconducting at temperatures up to ~40 K, by means of a novel hydrothermal method. The crystal structure is unambiguously determined by a combination of X-ray and neutron powder diffraction and nuclear magnetic resonance. Moreover, antiferromagnetic order is shown to coexist with superconductivity. This synthetic route opens a path for exploring superconductivity in other related systems, and confirms the appeal of iron selenides as a platform for understanding superconductivity in iron pnictides more broadly.
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS-CONDENSED MATTER
·
2021
·Vol. 33
·期 26
·265701
·
IF 2.333
Chengping He,Xue Ming,Qing Li,Xiyu Zhu,Jin Si,Hai-Hu Wen
Recently, superconductivity at about 9–15 K was discovered in Nd1−xSrxNiO2 (Nd-112, x ≈ 0.125–0.25) infinite-layer thin films, which has stimulated enormous interests in related rare-earth nickelates. Usually, the first step to synthesize this 112 phase is to fabricate the RNiO3 (R-113, R: rare-earth element) phase, however, it was reported that the 113 phase is very difficult to be synthesized successfully due to the formation of unusual Ni3+ oxidation state. And the difficulty of preparation is enhanced as the ionic radius of rare-earth element decreases. In this work, we report the synthesis and investigation on multiple physical properties of polycrystalline perovskites Sm1−xSrxNiO3 (x = 0, 0.2) in which the ionic radius of Sm3+ is smaller than that of Pr3+ and Nd3+ in related superconducting thin films. The structural and compositional analyses conducted by x-ray diffraction and energy dispersive x-ray spectrum reveal that the samples mainly contain the perovskite phase of Sm1−xSrxNiO3 with small amount of NiO impurities. Magnetization and resistivity measurements indicate that the parent phase SmNiO3 undergoes a paramagnetic–antiferromagnetic transition at about 224 K on a global insulating background. In contrast, the Sr-doped sample Sm0.8Sr0.2NiO3 shows a metallic behavior from 300 K down to about 12 K, while below 12 K the resistivity exhibits a slight logarithmic increase. Meanwhile, from the magnetization curves, we can see that a possible spin-glass state occurs below 12 K in Sm0.8Sr0.2NiO3. Using a soft chemical reduction method, we also obtain the infinite-layer phase Sm0.8Sr0.2NiO2 with square NiO2 planes. The compound shows an insulating behavior which can be described by the three-dimensional variable-range-hopping model. And superconductivity is still absent in the polycrystalline Sm0.8Sr0.2NiO2.
研究领域:
材料科学
·
凝聚态物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2021
·Vol. 31
·期 40
·2102917
·
IF 18.808
Ruijin Sun,Shifeng Jin,Jun Deng,Munan Hao,Xin Zhong,Yuxin Ma,Mingxing Li,Xiaolong Chen
High pressure has become a powerful platform for creating and controlling novel states of matter, including high temperature ( T c ) superconductivity. However, the emergent phenomena generally disappear as high pressure is removed and cloud prospects for future applications. Here, from a distinguishing perspective, FeSe 1− x S x is reported as 2D van der Waals materials with extraordinary high- T c at ambient pressure, where the superconductivity is boosted by extreme “chemical pressure” inside the materials. Superior to external high pressure, isovalent S substitution in FeSe leads to a much greater compression rate within the superconducting iron-chalcogenide layer, which guarantees an unabridged superconducting dome that peaked at 37.5 K. Density functional theory calculations reveal that the decreased lattice and structural parameters contribute together for the shift of Fe 3d x 2− y 2 orbital, which creates a new hole-pocket at the Fermi level that intimately correlated with the enhanced superconductivity. This study demonstrates the design of materials with optimized superconductivity by introducing chemical pressure.
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2023
·Vol. 129
·期 4
·1-10
·
IF 2.7
Luo Junsong,Guo Yiming,Liu Lian,Yu Zhou,Zhao Yong,Huang Mei,Xu Min,Duan Xuru,Zhang Yong
Nb 3 (Al 1– x Zn x ) ( x = 0–0.05) wires were obtained after single rapid heating, quenching and low temperature transformation (single-RHQT) process. It is found that Zn element can make crystal plane diffraction peaks of Nb 3 Al phase shift to higher angle, and the interplanar crystal spacing decreases gradually, which indicates that Al atoms in Nb 3 Al lattice are replaced by Zn atoms with smaller diameters. And the addition of Zn can reduce Δ T c and make the superconducting phases purer, and magnetic performances such as critical temperature ( T c ), critical current density ( J c ), irreversible field ( B irr ) are better than that of the pure sample. Nb 3 (Al 0.99 Zn 0.01 ) wire shows the highest J c value of about 5.9 × 10 4 A/cm 2 at 4.2 K and 8 T, and the highest T c value of 16.8 K was found in Nb 3 (Al 0.98 Zn 0.02 ). The influence of multiple rapid heating, quenching and low temperature transformation (multi-RHQT) process on Nb 3 (Al 1– x Zn x ) wires was mainly explored, and 2 at% and 3 at% Zn samples were selected with relatively high Δ T c values for five times RHQT treatment. It is observed that the multi-RHQT process can further reduce Δ T c , and more homogeneous superconducting phases are discovered compared with that of single-RHQT process. The elements are also evenly distributed in the multi-RHQT-processed Nb 3 (Al 1– x Zn x ) wires, leading to the improvement of J c , B irr performances compared to single-RHQT samples. Multi-RHQT-processed Nb 3 (Al 0.98 Zn 0.02 ) and Nb 3 (Al 0.97 Zn 0.03 ) samples show the J c values of 1.7 × 10 5 A/cm 2 and 1.2 × 10 5 A/cm 2 (4.2 K, 8 T), which are nearly ten times as many as that of single-RHQT samples, and Nb 3 (Al 0.97 Zn 0.03 ) has the highest B irr values of 19.6 T (4.2 K) and 10.7 T (10 K). Flux pinning of the Nb 3 (Al 1– x Zn x ) ( x = 0.01–0.05) wires follows the surface pinning mechanism, where grain boundary and stacking faults are considered as pinning centers.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Chinese Physics B
·
2025
·
IF 1.5
Xiaoci Ma,Yutong Hou,Keyu Shi,Jiaqi Zhang,Gaoping Yue,Qiang Tao,Yufei Ge,Pinwen Zhu
Electrically conductive carbide ceramics with high hardness and fracture toughness are promising for advanced applications. However, enhancing both electrical conductivity and fracture toughness simultaneous is challenging. This study reports the synthesis of (Ti0.2W0.2Ta0.2Hf0.2Mo0.2)C-diamond composites with varying densities using high-pressure and high-temperature (HPHT) method. The carbides are uniformly dispersed in a titanium carbide matrix, forming conductive channels that reduce resistivity to 4.6×10-7 Ω·m. These composite materials exhibit metallic conductivity with a superconducting transition at 8.5 K. Superconducting behavior may result from d-p orbital hybridization and electron-phonon coupling in transition metal carbides, such as TaC, Mo2C, and MoC. Optimizing intergranular bonding improves the fracture toughness without compromising hardness. The highest indentation toughness value is 10.1 ± 0.4 MPa·m1/2, a 130 % increase compare to pure TiC. Enhanced toughness arises from transgranular and intergranular fracture modes, multiple crack bridging, and large- angle crack deflection, which dissipate fracture energy and inhibit crack propagation. This study introduces a novel microstructure engineering strategy for carbide ceramics to achieve superior mechanical and electrical properties.
研究领域:
材料科学
·
固体力学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）