Tunable Fano and Dicke effects in quantum transport of double quantum dots sandwiched between topological insulators

Abstract

We study the quantum transport in double quantum dots (DQD) sandwiched between surfaces of topological insulator (TI) Bi${}_2$Te${}_3$, which possess strong spin-orbit coupling (SOC) and ${}^d$C${}_{3v}$ double group symmetry. Different from the spin-conserved case with two-dimensional electron gas (2DEG) electrodes, the conductance displays a universal scaling relation for different Fermi energy associated with the topological nature/linear dispersion of topological surface states. The interplay between direct inter-dot tunneling and surface state mediated interaction leads to tunable Dicke and Fano effects with changing the inter-dot distance. We propose nano-rulers with different measurement range and resolution based on the Fano $q$-factor. Furthermore, when applying an in-plane Zeeman field, a crossover from a double-peak shape to a quad-peak shape in conductance curve appears. Moreover, the rotational symmetry of the system could also be revealed from the conductance pattern. Our findings contribute to a better understanding of the quantum transport in the presence of electrode's SOC topological states.

arXiv comment7 pages, 6 figures

References in corpus (21)

• Topological Insulators
• Topological insulators and superconductors
• Topological Insulators in Three Dimensions
• Fano resonances in nanoscale structures
• Spins in few-electron quantum dots
• Model Hamiltonian for Topological Insulators
• Hexagonal Warping Effects in the Surface States of Topological Insulator Bi${}_2$Te${}_3$
• Dirac Semimetals in Two Dimensions
• Tunable Fano effect in parallel-coupled double quantum dot system
• Controlling Fano and Dicke effects via a magnetic flux in a double quantum-dot molecule
• Spin-resolved thermal signatures of Majorana-Kondo interplay in double quantum dots
• Study of 0-$\pi$ phase transition in hybrid superconductor-InSb nanowire quantum dot devices
• Fano Effect through Parallel-coupled Double Coulomb Islands
• Effects of the Dirac cone tilt in two-dimensional Dirac semimetal
• Manipulating Majorana zero modes in double quantum dots
• Josephson current via spin and orbital states of a tunable double quantum dot
• Extraordinary electron transmission through a periodic array of quantum dots
• Control of dephasing in spin qubits during coherent transport in silicon
• Spectroscopy of the local density-of-states in nanowires using integrated quantum dots
• Metastability and quantum coherence-assisted sensing in interacting parallel quantum dots
• Spin-dependent coherent transport in a double quantum dot system