We investigate the band structure and Goos–Hänchen-like shift in ferromagnetic mass graphene junction modulated by the circularly polarized light.It is found that both spin and valley-related energy gaps can be ...We investigate the band structure and Goos–Hänchen-like shift in ferromagnetic mass graphene junction modulated by the circularly polarized light.It is found that both spin and valley-related energy gaps can be opened by employing the circularly polarized light and the exchange field in mass graphene.The valley-polarized Goos–Hänchen-like shift can be identified in the presence of circularly polarized light,and the spin-polarized Goos–Hänchen-like shift can be realized with introduction of exchange field in mass graphene.Furthermore,the spin and valley polarization-related Goos–Hänchen-like shift can be achieved by combination of circularly polarized light and exchange field in mass graphene.It is hopeful that our work will be more conducive for future applications in graphene polarization transport devices.展开更多
We investigate theoretically the spin-dependent electron transport in a straight waveguide with Rashba spin-orbit coupling （SOC） under the irradiation of a transversely polarized electromagnetic （EM） field. Spin-d...We investigate theoretically the spin-dependent electron transport in a straight waveguide with Rashba spin-orbit coupling （SOC） under the irradiation of a transversely polarized electromagnetic （EM） field. Spin-dependent electron conductance and spin polarization are calculated as functions of the emitting energy of electrons or the strength of the EM field by adopting the mode matching approach. It is shown that the spin polarization can be manipulated by external parameters when the strength of Rashba SOC is strong. Furthermore, a sharp step structure is found to exist in the total electron conductance. These results can he understood by the nontrivial Rashba subbands intermixing and the electron intersubband transition when a finite-range transversely polarized EM field irradiates a straight waveguide.展开更多
The transport properties of a Dirac semimet^l quantum wire with two side gates are theoretically studied by adopting the lattice Green function method. It is found that a residual conductance quantum contributed from ...The transport properties of a Dirac semimet^l quantum wire with two side gates are theoretically studied by adopting the lattice Green function method. It is found that a residual conductance quantum contributed from the surface states can be switched on or off by tuning the electron energy or the side gates voltage. This ideal switching effect for the surface Dirac electron results from the transversal quantum confinement of the quantum wire in combination with the electrostatic potential induced by the side gates. These findings may provide useful guidance for designing all-electrical topological nanoelectronic devices.展开更多
We theoretically study the spin-dependent electron transport in a Rashba electron waveguide with rough edges,attached to ideal leads without spin-orbit interaction.The influence of the edge disorder on the charge and ...We theoretically study the spin-dependent electron transport in a Rashba electron waveguide with rough edges,attached to ideal leads without spin-orbit interaction.The influence of the edge disorder on the charge and spin conductances is clarified by using the spin-resolved lattice Green function method.It is found that a spin-polarized current can be generated in the output lead and its spin polarization can be manipulated by varying the waveguide length.The underlying physics is attributed to the broken longitudinal symmetry and the spin-dependent quantum interference induced by the rough boundaries.Our results may provide a new method to design a spin filter without using magnetic materials or applying a magnetic field.展开更多
We study the Goos-Hanchen-like shift of single silicene barrier under the external perpendicular electric field,off- resonant circularly polarized light and the exchange field modulation using the stationary-phase met...We study the Goos-Hanchen-like shift of single silicene barrier under the external perpendicular electric field,off- resonant circularly polarized light and the exchange field modulation using the stationary-phase method.The results show that the Goos-Hanchen-like shift of silicene resulting from the external perpendicular electric field does not have the characteristics of spin or valley polarization,while that from off-resonant circularly polarized light or the exchange field is spin-polarized.More importantly,the combined effect of the external perpendicular electric field and the exchange field or off-resonant circularly polarized light can cause the Goos-Hanchen-like shift of the system to be spin and valley polarized.It is particularly worth noting that when the three modulations are considered at the same time,as the exchange field changes,the system will have a positive or negative Goos-Hanchen-like shift.展开更多
基金the Natural Science Foundation of Jiangxi Province,China(Grant Nos.20224BAB201025 and 20202BABL201018)the National Natural Science Foundation of China(Grant Nos.11864012,11764013,and 12164021).
文摘We investigate the band structure and Goos–Hänchen-like shift in ferromagnetic mass graphene junction modulated by the circularly polarized light.It is found that both spin and valley-related energy gaps can be opened by employing the circularly polarized light and the exchange field in mass graphene.The valley-polarized Goos–Hänchen-like shift can be identified in the presence of circularly polarized light,and the spin-polarized Goos–Hänchen-like shift can be realized with introduction of exchange field in mass graphene.Furthermore,the spin and valley polarization-related Goos–Hänchen-like shift can be achieved by combination of circularly polarized light and exchange field in mass graphene.It is hopeful that our work will be more conducive for future applications in graphene polarization transport devices.
基金Project supported by the National Natural Science Foundation of China (Grant No 10774112)by the Science Foundation for Young Scientists of Jiangxi Agricultural University,China (Grant No 2219)
文摘We investigate theoretically the spin-dependent electron transport in a straight waveguide with Rashba spin-orbit coupling （SOC） under the irradiation of a transversely polarized electromagnetic （EM） field. Spin-dependent electron conductance and spin polarization are calculated as functions of the emitting energy of electrons or the strength of the EM field by adopting the mode matching approach. It is shown that the spin polarization can be manipulated by external parameters when the strength of Rashba SOC is strong. Furthermore, a sharp step structure is found to exist in the total electron conductance. These results can he understood by the nontrivial Rashba subbands intermixing and the electron intersubband transition when a finite-range transversely polarized EM field irradiates a straight waveguide.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11264019,11364019 and 11464011the Natural Science Foundation of Jiangxi Province under Grant No 20151BAB202007
文摘The transport properties of a Dirac semimet^l quantum wire with two side gates are theoretically studied by adopting the lattice Green function method. It is found that a residual conductance quantum contributed from the surface states can be switched on or off by tuning the electron energy or the side gates voltage. This ideal switching effect for the surface Dirac electron results from the transversal quantum confinement of the quantum wire in combination with the electrostatic potential induced by the side gates. These findings may provide useful guidance for designing all-electrical topological nanoelectronic devices.
基金Supported by the National Natural Science Foundation of China under Grant No 10832005the China Postdoctoral Science Foundation under Grant No 20100481188the Research Foundation of Jiangxi Education Department under Grant No GJJ12532.
文摘We theoretically study the spin-dependent electron transport in a Rashba electron waveguide with rough edges,attached to ideal leads without spin-orbit interaction.The influence of the edge disorder on the charge and spin conductances is clarified by using the spin-resolved lattice Green function method.It is found that a spin-polarized current can be generated in the output lead and its spin polarization can be manipulated by varying the waveguide length.The underlying physics is attributed to the broken longitudinal symmetry and the spin-dependent quantum interference induced by the rough boundaries.Our results may provide a new method to design a spin filter without using magnetic materials or applying a magnetic field.
基金supported by the National Natural Science Foundation of China(Grant Nos.11864012 and 11764013)the Natural Science Foundation of Jiangxi Province,China(Grant No.20202BABL201018)Jiangxi University of Traditional Chinese Medicine 1050 Youth Talent Project(Grant No.5142001010)。
文摘We study the Goos-Hanchen-like shift of single silicene barrier under the external perpendicular electric field,off- resonant circularly polarized light and the exchange field modulation using the stationary-phase method.The results show that the Goos-Hanchen-like shift of silicene resulting from the external perpendicular electric field does not have the characteristics of spin or valley polarization,while that from off-resonant circularly polarized light or the exchange field is spin-polarized.More importantly,the combined effect of the external perpendicular electric field and the exchange field or off-resonant circularly polarized light can cause the Goos-Hanchen-like shift of the system to be spin and valley polarized.It is particularly worth noting that when the three modulations are considered at the same time,as the exchange field changes,the system will have a positive or negative Goos-Hanchen-like shift.
