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We theoretical investigate the electron transport through HgTe/CdTe quantum wells (QWs) heterostructure interfaces with periodic electrical potential modulations in this work. We find Fabry–Pérot resonant tunneling with perfect transmission through a two dimensional topological insulator superlattice structure in HgTe/CdTe QWs, which is supposed to be experimentally observable. This unique feature indicates potential applications of Fabry–Pérot interferometers device. The transport properties of electrons tunneling through the superlattice structures can be adjusted by tuning the Fermi energy, electron incident angle, the electrical modulation numbers and modulation amplitude. We also find the enhanced Fabry–Pérot resonance tunneling due to the electric-induced Rashba spin–orbit interaction (RSOI). This all-electrical mechanism may pave a realistic way to control the electron transport in two dimension topological insulator from a device application perspective. • We find Fabry-Pérot resonant tunneling with perfect transmission through a two dimensional topological insulator superlattice structure in HgTe/CdTe QWs, which is supposed to be experimentally observable. • This unique feature indicates potential applications of Fabry-Perot interferometers device. • We also find the enhanced Fabry-Perot resonance tunneling due to the electric-induced Rashba spin-orbit interaction (RSOI). • This all-electrical mechanism may pave a realistic way to control the electron transport in two dimension topological insulator from a device application perspective. [ABSTRACT FROM AUTHOR]

We investigate theoretically the electron transport through (001) HgTe/CdTe quantum well heterostructures with inverted-band in planar geometry, where Dirac-like spin–momentum locked interface states have been predicted to be formed and topologically protected against perturbations preserving time-reversal symmetry. In this work, k.p theory and scattering matrix method are used to characterize the interface states of the (001) HgTe/CdTe heterostructure as well as to understand the influence of external electric fields. We find distinct features of the transmission and conductance by considering both Rashba and Dresselhuas spin–orbit interactions. The efficient spin–flip conversion between spin-up and spin-down channels are found by tuning the strength of Rashba and Dresselhuas spin–orbit interactions. It is shown that ideal spin–flip efficiency, i.e., the complete spin–flip, can be achieved with specific spin–orbit coupling strengths. This spin–flip mechanism provides us a realistic way to manipulate the spin orientation which can be constructed low-power information processing device. Furthermore, we address the topological edge states induced unique spin manipulation capability by comparing with the conventional electron transport properties in bulk states. In addition, we analyze the transport behavior when the system in the presence of Zeeman term which may play an important role for a high magnetic field in a realistic experimental setup. • We investigated theoretically the transport properties of carriers through inverted-band HgTe/CdTe topological interface states including Rashba and Dresselhuas SOI modulations. • The numerical results demonstrate effective modulation capability on the transmission probabilities by changing the RSOI and DSOI strengths. • The spin-flip conversion between the spin-up channel and the spin-down channel are found by considering both RSOI and DSOI modulations, and the complete spin-flip transmission can be achieved. • The SOI-induced spin-flip mechanism provides us a way to constructing low-power information processing device in topological insulator. [ABSTRACT FROM AUTHOR]

This work presents theoretically investigate the electron transport through a PN junction in two-dimensional HgTe/CdTe topological insulator. We find that the transmission can be tuned by changing the incidence angle, gate voltage, Fermi energy and the Rashba spin–orbit interaction (RSOI). By tuning the strength of RSOI modulation, the efficient spin-flip conversion for the spin-up and spin-down channels are found. Furthermore, a perfect one-channel transmission mode with T = 1 is formed due to the spin-split induced by the RSOI. This RSOI-induced spin-split mechanism provides us a way of pure electrical modulation to manipulate the spin and charge currents. • This work presents a theoretically investigation of the electron transport through a PN junction in two-dimensional topological insulator transistor made by a HgTe/CdTe quantum well with inverted-band structure. • We find distinct features of the transmission by considering the Rashba spin–orbit interaction (RSOI). • It is demonstrated that the transmission can be effectively tuned by changing the incidence angle, gate voltage, Fermi energy and the RSOI modulation. • By tuning the strength of RSOI modulation, the efficient spin-flip conversion for the spin-up channel and the spin-down channel are found. • A perfect one-channel transmission mode with T = 1 is formed due to the spin-split induced by the RSOI modulation. [ABSTRACT FROM AUTHOR]

Heterostructure transport properties is investigated theoretically based on two-dimensional planar HgTe/CdTe quantum wells structure by a dual-gate modulations. Two voltage gates is deposited on the top of the heterostructure to create the corresponding electrical modulation potential. The electron transport property is explored by calculating the transmission spectrum by tuning the incidence angle, Fermi energy and electrical modulation potential. It is demonstrated that the transmission probability can be effectively tuned by changing the incidence angle, gate voltage and Fermi energy. Our findings pave the way for possible future applications of topological insulator-based devices. • This work theoretically presents the transport investigation on the heterostructure based on 2D HgTe/CdTe quantum wells by a dual-gate modulations. • Two voltage gates is deposited on the top of the heterostructure to create the corresponding electrical modulation potential. • The electron transport property is explored by calculating the transmission spectrum by tuning the incidence angle, Fermi energy and electrical modulation potential. • It is demonstrated that the transmission probability can be effectively tuned by changing the incidence angle, gate voltage and Fermi energy. • Our findings pave the way for possible future applications of topological insulator-based devices. [ABSTRACT FROM AUTHOR]

Electron tunneling through a single magnetic barrier in a HgTe topological insulator has been theoretically investigated. We find that the perpendicular magnetic field would not lead to spin-flip of the edge states due to the conservation of the angular moment. By tuning the magnetic field and the Fermi energy, the edge channels can be transited from switch-on states to switch-off states and the current from unpolarized states can be filtered to fully spin polarized states. These features offer us an efficient way to control charge/spin transport in a HgTe/CdTe quantum well, and pave a way to construct the nanoelectronic devices utilizing the topological edge states. [ABSTRACT FROM AUTHOR]