Design principles for HgTe based topological insulator devices

Abstract

The topological insulator properties of CdTe/HgTe/CdTe quantum wells are theoretically studied. The CdTe/HgTe/CdTe quantum well behaves as a topological insulator beyond a critical well width dimension. It is shown that if the barrier(CdTe) and well-region(HgTe) are altered by replacing them with the alloy Cd${}_x$Hg${}_{1-x}$Te of various stoichiometries, the critical width can be changed.The critical quantum well width is shown to depend on temperature, applied stress, growth directions and external electric fields. Based on these results, a novel device concept is proposed that allows to switch between a normal semiconducting and topological insulator state through application of moderate external electric fields.

8 pages, 13 figures

References in corpus (9)

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Cited by in corpus (14)

• Efficient and realistic device modeling from atomic detail to the nanoscale
• Pressure and temperature driven phase transitions in HgTe quantum wells
• Temperature-induced topological phase transition in HgTe quantum wells
• Temperature-driven single-valley Dirac fermions in HgTe quantum wells
• Phonon-induced topological insulation
• Ab initio study of $Z_2$ topological phases in perovskite (111) $({\text{SrTiO}}_3{)}_7/({\text{SrIrO}}_3{)}_2$ and $({\text{KTaO}}_3{)}_7/({\text{KPtO}}_3{)}_2$ multilayers
• Temperature-dependent magnetospectroscopy of HgTe quantum wells
• First principles feasibility assessment of a topological insulator at the InAs/GaSb interface
• Superconducting Diode Effect in Quantum Spin Hall Insulator-based Josephson Junctions
• Realizing robust large-gap quantum spin Hall state in 2D HgTe monolayer on insulating substrate
• Asymmetric versus symmetric $HgTe/C{\mathrm{d}}_{\mathrm{x}}\mathrm{H}{\mathrm{g}}_{1-\mathrm{x}}\mathrm{Te}$ double quantum wells: Band gap tuning without electric field
• Cross-section geometry effects in the subband structure and spin-related properties of a HgTe/CdTe nanowire
• Formation of bound states from the edge states of 2D topological insulator by macroscopic magnetic barriers
• Hard wall edge confinement in 2D topological insulators and the energy of the Dirac Point