![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() by Staff Writers Beijing, China (SPX) Aug 13, 2018
In the past century, superconductivity has been observed in thousands of substances with multifarious chemical compositions and crystal structures; however, researchers have still not found an explicit method for discovering new superconductors. For the unconventional high-Tc superconductors of cuprates and iron pnictides/chalcogenides, the occurrence of superconductivity is highly related to the existence of some certain quasi-two-dimensional structural motifs, e.g., the CuO2 planes or the Fe2As2/Fe2Se2 layers. Thus, low dimensionality has generally been considered as a favorable ingredient for exotic electron pairing due to the enhancement of electronic correlations. While among the quasi-one-dimensional (Q1D) compounds, only a few compounds were found to be superconducting at considerably low temperatures of several degrees Kelvin. Recently, a team led by Prof. Zhian Ren from the Institute of Physics, Chinese Academy of Sciences discovered a Q1D superconductor K2Mo3As3, with a Tc value exceeding 10 K for the first time. Although lots of molybdenum chalcogenide superconductors were discovered from the 1970's, ternary compounds of molybdenum arsenide have rarely been reported. After many efforts on studying Mo-based ternary phases, the team succeeded in synthesizing the new K2Mo3As3 compound, which crystalizes in a noncentrosymmetric hexagonal structure with typical Q1D (Mo3As3)2- linear chains separated by K+ cations, similar to the structure of K2Mo3As3. Bulk superconductivity below 10.4 K was confirmed by electrical resistivity, magnetic susceptibility, and heat capacity measurements. The K2Mo3As3 is the first MoAs-based superconductor and possesses the record Tc in all Q1D superconductors. This discovery indicates that Cr and Mo based Q1D superconductors may share some common underlying origins within the similar structural motifs and will help to uncover the exotic superconducting mechanism in low dimensional materials. Qing-Ge Mu, Bin-Bin Ruan, Kang Zhao, Bo-Jin Pan, Tong Liu, Lei Shan, Gen-Fu Chen, Zhi-An Ren. Superconductivity at 10.4K in a novel quasi-one-dimensional ternary molybdenum pnictide K2Mo3As3. Science Bulletin, 2018, 63(15) 952-956, doi: 10.1016/j.scib.2018.06.011
![]() ![]() Chinese-American engineer charged with stealing GE technology Washington (AFP) Aug 2, 2018 A Chinese-American engineer faces charges of stealing valuable technology from General Electric, sneaking it out hidden in a picture of the sunset to take to China, the US Justice Department said. A federal judge on Thursday ordered that Xiaoqing Zheng, 56, be released Friday on $100,000 bond and placed under electronic monitoring while surrendering his passport, according to the United States Attorney's Office for the Northern District of New York. Zheng, a US citizen also believed to have Chin ... read more
![]() |
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |