Devices of electric double-layer transistors (EDLTs) with ionic liquid have been employed as an effective way to dope carriers over a wide range. However, the induced electronic states can hardly survive in the mate...Devices of electric double-layer transistors (EDLTs) with ionic liquid have been employed as an effective way to dope carriers over a wide range. However, the induced electronic states can hardly survive in the materials after releasing the gate voltage VG at temperatures higher than the melting point of the selected ionic liquid. Here we show that a permanent superconductivity with transition temperature Tc of 24 and 15K is realized hi single crystals and polycrystalline samples of HfNCI and ZrNCI upon applying proper VG's at different temperatures. Reversible change between insulating and superconducting states can be obtained by applying positive and negative VG at low temperature such as 220K, whereas VG 's applied at 250K induce the irreversible superconducting transition. The upper critical field He2 of the superconducting states obtained at different gating temperatures shows similar temperature dependence. We propose a reasonable scenario that partial vacancy of Cl ions could be caused by applying proper VG's at slightly higher processing temperatures, which consequently results in a permanent electron doping in the system. Such a technique shows great potential to systematically tune the bulk electronic state in the similar two-dimensional systems.展开更多
The single thiolated arylethynylene molecule with 9,10-dihydroanthracene core(denoted as TADHA) possesses pronounced negative differential conductance(NDC) behavior at lower bias regime. The adsorption effects of ...The single thiolated arylethynylene molecule with 9,10-dihydroanthracene core(denoted as TADHA) possesses pronounced negative differential conductance(NDC) behavior at lower bias regime. The adsorption effects of F2 molecule on the current and NDC behavior of TADHA molecular junctions are studied by applying non-equilibrium Green's formalism combined with density functional theory. The numerical results show that the F2 molecule adsorbed on the benzene ring of TADHA molecule near the electrode can dramatically suppresses the current of TADHA molecular junction. When the F2 molecule adsorbed on the conjugated segment of 9,10-dihydroanthracene core of TADHA molecule, an obviously asymmetric effect on the current curves induces the molecular system showing apparent rectifier behavior. However, the current especially the NDC behavior have been significantly enlarged when F2 addition reacted with triple bond of TADHA molecule.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11704403the National Key Research Program of China under Grant No 2016YFA0401000 and 2016YFA0300604the Strategic Priority Research Program(B)of Chinese Academy of Sciences under Grant No XDB07020100
文摘Devices of electric double-layer transistors (EDLTs) with ionic liquid have been employed as an effective way to dope carriers over a wide range. However, the induced electronic states can hardly survive in the materials after releasing the gate voltage VG at temperatures higher than the melting point of the selected ionic liquid. Here we show that a permanent superconductivity with transition temperature Tc of 24 and 15K is realized hi single crystals and polycrystalline samples of HfNCI and ZrNCI upon applying proper VG's at different temperatures. Reversible change between insulating and superconducting states can be obtained by applying positive and negative VG at low temperature such as 220K, whereas VG 's applied at 250K induce the irreversible superconducting transition. The upper critical field He2 of the superconducting states obtained at different gating temperatures shows similar temperature dependence. We propose a reasonable scenario that partial vacancy of Cl ions could be caused by applying proper VG's at slightly higher processing temperatures, which consequently results in a permanent electron doping in the system. Such a technique shows great potential to systematically tune the bulk electronic state in the similar two-dimensional systems.
基金Project supported by the National Natural Science Foundation of China(Grant No.11374195)the Taishan Scholar Project of Shandong Province,Chinathe Jinan Youth Science and Technology Star Project,China(Grant No.201406004)
文摘The single thiolated arylethynylene molecule with 9,10-dihydroanthracene core(denoted as TADHA) possesses pronounced negative differential conductance(NDC) behavior at lower bias regime. The adsorption effects of F2 molecule on the current and NDC behavior of TADHA molecular junctions are studied by applying non-equilibrium Green's formalism combined with density functional theory. The numerical results show that the F2 molecule adsorbed on the benzene ring of TADHA molecule near the electrode can dramatically suppresses the current of TADHA molecular junction. When the F2 molecule adsorbed on the conjugated segment of 9,10-dihydroanthracene core of TADHA molecule, an obviously asymmetric effect on the current curves induces the molecular system showing apparent rectifier behavior. However, the current especially the NDC behavior have been significantly enlarged when F2 addition reacted with triple bond of TADHA molecule.