A Simple Urea Approach to N-Dopedα-Mo_(2)C with Enhanced Superconductivity  

作　　者：Longfu Li Lei Shi Lingyong Zeng Kuan Li Peifeng Yu Kangwang Wang Chao Zhang Rui Chen Zaichen Xiang Yunwei Zhang Huixia Luo 李龙夫;石磊;曾令勇;李宽;余沛峰;王康旺;张超;陈睿;项载琛;张云蔚;罗惠霞(School of Materials Science and Engineering,State Key Laboratory of Optoelectronic Materials and Technologies,Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices,Key Lab of Polymer Composite&Functional Materials,Sun Yat-Sen University,Guangzhou 510275,China;School of Physics,Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices,Sun Yat-Sen University,Guangzhou 510275,China)

机构地区：[1]School of Materials Science and Engineering,State Key Laboratory of Optoelectronic Materials and Technologies,Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices,Key Lab of Polymer Composite&Functional Materials,Sun Yat-Sen University,Guangzhou 510275,China [2]School of Physics,Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices,Sun Yat-Sen University,Guangzhou 510275,China

出　　处：《Chinese Physics Letters》2024年第10期103-111,共9页中国物理快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.12274471 and 11922415);Guangdong Basic and Applied Basic Research Foundation(Grant No.2022A1515011168);the Key Research&Development Program of Guangdong Province,China(Grant No.2019B110209003);the Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices(Grant Nos.2022B1212010008);Lingyong Zeng was supported by the Postdoctoral Fellowship Program of CPSF(Grant Nos.GZC20233299);Fundamental Research Funds for the Central Universities,Sun Yat-Sen University(Grant Nos.29000-31610058)。

摘　　要：Chemical doping is a critical factor in the development of new superconductors or optimizing the superconducting transition temperature(T_(c))of the parent superconducting materials.Here,a new simple urea approach is developed to synthesize the N-dopedα-Mo_(2)C.Benefiting from the simple urea method,a broad superconducting dome is found in the Mo_(2)C_(1−x)N_(x)(0≤x≤0.49)compositions.X-ray diffraction results show that the structure of𝛼α-Mo_(2)C remains unchanged and there is a variation of lattice parameters with nitrogen doping.Resistivity,magnetic susceptibility,and heat capacity measurement results confirm that T_(c)was strongly increased from 2.68K(x=0)to 7.05K(x=0.49).First-principles calculations and our analysis indicate that increasing nitrogen doping leads to a rise in the density of states at the Fermi level and doping-induced phonon softening,which enhances electron–phonon coupling.This results in an increase in𝑇T_(c)and a sharp rise in the upper critical field.Our findings provide a promising strategy for fabricating transition metal carbonitrides and provide a material platform for further study of the superconductivity of transition metal carbides.

关 键 词：SOFTENING DOPING CRITICAL 

分 类 号：O511.3[一般工业技术—材料科学与工程]