Goos-Hänchen-like shift in biased silicene

Abstract

We have theoretically studied the Goos-Hänchen-like shift of spinor-unpolarized beams tunneling through various gate-biased silicene nanostructures. Following the stationary-phase method, lateral displacement in single-, dual-, and multiple-gated silicene systems has been systematically demonstrated. It is shown for simple single-gated silicene that lateral displacement can be generally enhanced by Fabry-Perot interference, and near the transition point turning on the evanescent mode a very large lateral shift could be observed. For the dual-gated structure, we have also shown the crucial role of localized modes like quantum well states in enhancing the beam lateral displacement, while for the multiple gate-biased systems the resulting superlattice subbands are also favorable for lateral displacement enhancement. Importantly, including the degeneracy-broken mechanisms such as gate-field and magnetic modulations, a fully spinor-resolved beam can be distinguished from the rest counterparts by aligning the incident beam with a proper spinor-resolved transition point, localized state, and subband, all of which can be flexibly modulated via electric means, offering the very desirable strategies to achieve the fully spinor-polarized beam for functional electronic applications.

Goos–Hänchen-like shift related to spin and valley polarization in ferromagnetic silicene*

“…[22,23] It has demonstrated that for a normal/ferromagnetic/normal silicene junction, the GHL shift is negative and positive. [24,25] However, there are few further studies on simultaneous valley-and spin-polarized GHL shift in silicene. Recently, it is reported that the off-resonant circularly polarized light can open a band gap of the Dirac cone in silicene, [26][27][28] which can lead to the valley separation.…”

Nano‐scale multifunctional logic gate based on graphene/hexagonal boron nitride plasmonic waveguides

“…Recently, various metamaterials such as black phosphorus, silicene, and graphene have been used to increase the efficiency of multifunctional logic gates [27,28]. Special attention has been paid to graphene because it is the most promising candidate when tunability is important [29,30].…”

A high-quality spin and valley beam splitter in WSe2 tunnelling junction through the Goos–Hänchen shift

“…During the past five years, the graphene counter parts, including silicene, transitionmetal dichalcogenides (TMDCs), and phosphorene, etc. have been successively syn thesized in experiment, making the study of opticslike phe nomena in 2D materials to be an emerging topic [12][13][14][15]. In contrast to graphene, the TMDCs such as WSe 2 have a strong spin-orbit coupling (SOC) (2λ c = 30 meV for the conduc tion band edge and 2λ v = 450 meV for the valence band edge [16]) originated from the d orbital of the heavy metal atoms [17].…”