In 1964, American scientist Little theory predicted organic compounds have superconductivity and its superconducting transition temperature can reach room temperature, which aroused the researchers' enthusiasm for organic superconductors.The first organic superconductor (TMTSF) 2PF6 was discovered in the 20th century In the era of organic superconductors, there are mainly three types of organic superconductors: organic charge transfer salts (TMTSF) 2PF6, superconductors based on carbon materials and superconductors of organic compounds based on benzenes. Due to the low dimensional nature of organic superconductors, strong electron- Interaction and electron-phonon interaction, novel physical phenomena such as three-dimensional quantum effect and spin liquid behavior can be observed in organic superconductors.In order to search for superconducting materials with higher superconducting transition temperatures, new organic Superconducting material system is still an important goal of superconductivity research.
Recently, researchers from the CAS Solid State Key Laboratory of Organic Solid State Academies and the State Key Laboratory of Superconductivity at the Institute of Physics of the Chinese Academy of Sciences found that the resistance of the Cu-BHT thin film with the structure shown in FIG. 1 decreased to 0 ; Entering the superconducting state, the diamagnetic transition observed in the AC susceptibility test and the phase transition observed in the specific heat test confirm that Cu-BHT is a superconductor with a transition temperature of 0.25 K. Meanwhile, the direct observation using STEM The atomic image of Cu-BHT confirms its perfect Kagome structure. This Kagome lattice may lead to the spin-fluctuation behavior of Cu-BHT at low temperature. Although the superconducting transition temperature is lower, Cu-BHT is the first Metal-organic coordination polymer superconductors, which appear to expand the organic superconductor material system, provided a new possibility for the study of organic superconductors; while in Cu-BHT observed in the low temperature spin disturbance also indicates Cu- More novel quantum states may appear in BHT.
Relevant research results were published in Angew. Chem. Int. Ed. The research has been funded by the National Natural Science Foundation of China, Ministry of Science and Technology, Chinese Academy of Sciences.
Figure 1. Cu-BHT structure
Figure 2. Superconductance and TEM, STEM characterization of Cu-BHT a. The resistance of the Cu-BHT thin film drops to 0 below 0.25 K. b. The diamagnetic transition observed in AC susceptibility testing c. Specific heat D, Kagome lattice may lead to spin-fluctuation behavior of Cu-BHT at low temperature; gh, direct observation of the atomic image of Cu-BHT by STEM
