We investigate the time-modulated electronic and spin transport properties through two T-shaped three-quantum-dot molecules embedded in an Aharonov-Bohm（A-B） interferometer. By using the Keldysh non-equilibrium Gree...We investigate the time-modulated electronic and spin transport properties through two T-shaped three-quantum-dot molecules embedded in an Aharonov-Bohm（A-B） interferometer. By using the Keldysh non-equilibrium Green＇s function technique, the photon-assisted spin-dependent average current is analyzed. The T-shaped three-quantum-dot molecule A-B interferometer exhibits excellent controllability in the average current resonance spectra by adjusting the interdot coupling strength, Rashba spin-orbit coupling strength, magnetic flux, and amplitude of the time-dependent external field.Efficient spin filtering and multiple electron-photon pump functions are exploited in the multi-quantum-dot molecule A-B interferometer by a time-modulated external field.展开更多
Using the non-equilibrium Keldysh Green＇s function technique, we investigate electron transport properties of a system consisting of multiple three-quantum-dot rings. The conductance as a function of the electron ene...Using the non-equilibrium Keldysh Green＇s function technique, we investigate electron transport properties of a system consisting of multiple three-quantum-dot rings. The conductance as a function of the electron energy is numerically calculated. An antiresonance point emerges in the conductance spectra and evolves into a well-defined insulating band with the increasing number of three-quantum-dot rings. The position of the well-defined insulating band can be modulated by varying the tunneling coupling strength between adjacent three-quantum-dot rings. When an external magnetic flux is introduced, several to 100% spin-polarized windows will occur due to the Zeeman splitting. These results strongly suggest that this device may realize multiple functions including quantum switch and efficient spin filtering.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11447132 and 11504042)the Natural Science Foundation of Heilongjiang,China(Grant No.A201405)+2 种基金111 Project to Harbin Engineering University,China(Grant No.B13015)Chongqing Science and Technology Commission Project,China(Grant Nos.cstc2014jcyj A00032 and cstc2016jcyj A1158)Scientific Research Project for Advanced Talents of Yangtze Normal University,China(Grant No.2017KYQD09)
文摘We investigate the time-modulated electronic and spin transport properties through two T-shaped three-quantum-dot molecules embedded in an Aharonov-Bohm（A-B） interferometer. By using the Keldysh non-equilibrium Green＇s function technique, the photon-assisted spin-dependent average current is analyzed. The T-shaped three-quantum-dot molecule A-B interferometer exhibits excellent controllability in the average current resonance spectra by adjusting the interdot coupling strength, Rashba spin-orbit coupling strength, magnetic flux, and amplitude of the time-dependent external field.Efficient spin filtering and multiple electron-photon pump functions are exploited in the multi-quantum-dot molecule A-B interferometer by a time-modulated external field.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11447132 and 11504042, the Natural Science Foundation of Heilongjiang Province under Grant No A201405, Chongqing Science and Technology Commission Project under Grant Nos cstc2014jcyjA00032 and cstc2016jcyjA1158, and the Scientific Research Project for Advanced Talents of Yangtze Normal University under Grant No 2017KYQD09.
文摘Using the non-equilibrium Keldysh Green＇s function technique, we investigate electron transport properties of a system consisting of multiple three-quantum-dot rings. The conductance as a function of the electron energy is numerically calculated. An antiresonance point emerges in the conductance spectra and evolves into a well-defined insulating band with the increasing number of three-quantum-dot rings. The position of the well-defined insulating band can be modulated by varying the tunneling coupling strength between adjacent three-quantum-dot rings. When an external magnetic flux is introduced, several to 100% spin-polarized windows will occur due to the Zeeman splitting. These results strongly suggest that this device may realize multiple functions including quantum switch and efficient spin filtering.
