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
By solving the Bogoliubov-de Gennes equation, the influence of the interplay of Rashba spin-orbit coupling, induced superconducting pair potential, and external magnetic field on the spin-polarized coherent charge tra...By solving the Bogoliubov-de Gennes equation, the influence of the interplay of Rashba spin-orbit coupling, induced superconducting pair potential, and external magnetic field on the spin-polarized coherent charge transport in ferromagnet/semiconductor nanowire/ferromagnet double barrier junctions is investigated based on the Blonder-Tinkham-Klapwijk theory. The coherence effect is characterized by the strong oscillations of the charge conductance as a function of the bias voltage or the thickness of the semiconductor nanowire, resulting from the quantum interference of incoming and outgoing quasiparticles in the nanowire. Such oscillations can be effectively modulated by varying the strength of the Rashba spin-orbit coupling, the thickness of the nanowire, or the strength of the external magnetic field. It is also shown that two different types of zero-bias conductance peaks may occur under some particular conditions, which have some different characteristics and may be due to different mechanisms.展开更多
Using the four-probe method, we investigate the electrical conductivity of Cu3N under high pressure with the diamond anvil cell. Cu3N is a semiconductor at ambient pressure showing a band gap about l eV. With the appl...Using the four-probe method, we investigate the electrical conductivity of Cu3N under high pressure with the diamond anvil cell. Cu3N is a semiconductor at ambient pressure showing a band gap about l eV. With the application of quasi-hydrostatic pressures, its resistance decreases dramatically over five orders of magnitude from ambient to 9 GPa. The compound became a metal at pressure about 5.5 GPa, which is in well agreement with the recent first principle calculation.展开更多
In this paper, we briefly go over the homogeneous 5D model field theory: from the 5D space-time inception, to its quantum field solutions given in terms of Higgs vacuum, filled with magnetic monopole bose fields of al...In this paper, we briefly go over the homogeneous 5D model field theory: from the 5D space-time inception, to its quantum field solutions given in terms of Higgs vacuum, filled with magnetic monopole bose fields of all energies. Then through the space dimension reduction projections, the Gell-Mann standard model was obtained as well as a quantum to Classical connection was made via introducing Bose distribution to the monopoles to obtain the Perelman entropy and Ricci Flow mappings. This provided us a picture to the creation of Astronomical objects, from galaxies to stars and planets. This method of splitting the monopole energy into ranges is extended to show that below the basic rest mass range of the electron and Quark, it still can be applied to explaining for the creation of the chemical elements periodic table. But perhaps the most interesting is in the lowest hundreds of Hz energy range, obtained from yet another 3 fold space symmetry breaking, into 2D × 1D, producing bio nitrogenous bases composed of 3 Carbon 12 in hexagon structures, due to preservation of the 1D monopole standing waves of this low frequencies. From that by imposing gauge changes the monopole states into DNA spectra. Since such spectra states retain the DLRO, it induces formation of charge carriers periodicity in a spherical bio cell.. It was then argued that due to cell’s surface proteins, the structure must contain partial filled VB, with “p” state hole density, and empty CB, separated from VB by a positive band gap. Such band structures resemble known HTC Cuprate ceramics. Since the HTC goes through a Superconductivity transition via the simultaneous bose exciton condensation, providing a Coulomb pressure, which reduces the band gap substantially, and induces the ODLRO transition of the hole density. The same obviously applies to the bio cells. Because of the near continuous exciton levels generated, a matching to the DNA spectra then can always occur by selective choices of proteins on the cell surface. Judging from a numerical study, we did years ago on YBCO, with doping. We found with a large enough VB hole density, the exciton induced superconducting gap can easily lead to <em>T</em><em>c</em> in the room temperature range. In fact by EMF excitation can increase the exciton pressure and trigger the ODLRO transition <em>T</em><em>c</em> upward. In fact, numerical results then suggest there do exist coherent EMF spectra from three key elements: Water, Carbon and Hydrogen, together with Oxygen, as studied over the years by numerous people, starting from Schr<span style="white-space:nowrap;">ö</span>dinger to most recently Geesink.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.
文摘By solving the Bogoliubov-de Gennes equation, the influence of the interplay of Rashba spin-orbit coupling, induced superconducting pair potential, and external magnetic field on the spin-polarized coherent charge transport in ferromagnet/semiconductor nanowire/ferromagnet double barrier junctions is investigated based on the Blonder-Tinkham-Klapwijk theory. The coherence effect is characterized by the strong oscillations of the charge conductance as a function of the bias voltage or the thickness of the semiconductor nanowire, resulting from the quantum interference of incoming and outgoing quasiparticles in the nanowire. Such oscillations can be effectively modulated by varying the strength of the Rashba spin-orbit coupling, the thickness of the nanowire, or the strength of the external magnetic field. It is also shown that two different types of zero-bias conductance peaks may occur under some particular conditions, which have some different characteristics and may be due to different mechanisms.
基金Support.ed by National Natural Science Foundation of China under Grang Nos 50321101, 50332020 and 50328102, and the National Key Basic Research and Development. Programme of China under Grant Nos 2002CB613301 and 2005CB724402. We thank Professor L. C. Chen and R. Z. Che for helpful discussion.
文摘Using the four-probe method, we investigate the electrical conductivity of Cu3N under high pressure with the diamond anvil cell. Cu3N is a semiconductor at ambient pressure showing a band gap about l eV. With the application of quasi-hydrostatic pressures, its resistance decreases dramatically over five orders of magnitude from ambient to 9 GPa. The compound became a metal at pressure about 5.5 GPa, which is in well agreement with the recent first principle calculation.
文摘In this paper, we briefly go over the homogeneous 5D model field theory: from the 5D space-time inception, to its quantum field solutions given in terms of Higgs vacuum, filled with magnetic monopole bose fields of all energies. Then through the space dimension reduction projections, the Gell-Mann standard model was obtained as well as a quantum to Classical connection was made via introducing Bose distribution to the monopoles to obtain the Perelman entropy and Ricci Flow mappings. This provided us a picture to the creation of Astronomical objects, from galaxies to stars and planets. This method of splitting the monopole energy into ranges is extended to show that below the basic rest mass range of the electron and Quark, it still can be applied to explaining for the creation of the chemical elements periodic table. But perhaps the most interesting is in the lowest hundreds of Hz energy range, obtained from yet another 3 fold space symmetry breaking, into 2D × 1D, producing bio nitrogenous bases composed of 3 Carbon 12 in hexagon structures, due to preservation of the 1D monopole standing waves of this low frequencies. From that by imposing gauge changes the monopole states into DNA spectra. Since such spectra states retain the DLRO, it induces formation of charge carriers periodicity in a spherical bio cell.. It was then argued that due to cell’s surface proteins, the structure must contain partial filled VB, with “p” state hole density, and empty CB, separated from VB by a positive band gap. Such band structures resemble known HTC Cuprate ceramics. Since the HTC goes through a Superconductivity transition via the simultaneous bose exciton condensation, providing a Coulomb pressure, which reduces the band gap substantially, and induces the ODLRO transition of the hole density. The same obviously applies to the bio cells. Because of the near continuous exciton levels generated, a matching to the DNA spectra then can always occur by selective choices of proteins on the cell surface. Judging from a numerical study, we did years ago on YBCO, with doping. We found with a large enough VB hole density, the exciton induced superconducting gap can easily lead to <em>T</em><em>c</em> in the room temperature range. In fact by EMF excitation can increase the exciton pressure and trigger the ODLRO transition <em>T</em><em>c</em> upward. In fact, numerical results then suggest there do exist coherent EMF spectra from three key elements: Water, Carbon and Hydrogen, together with Oxygen, as studied over the years by numerous people, starting from Schr<span style="white-space:nowrap;">ö</span>dinger to most recently Geesink.