Tailoring topological states of core-shell nanoparticles
arXiv:2105.13064 · doi:10.1016/j.physe.2021.115000
Abstract
In this work we investigate novel spherical core-shell nanoparticles with band inversion. The core and the embedding medium are normal semiconductors while the shell material is assumed to be a topological insulator. The envelope functions are found to satisfy a Dirac-like equation that can be solved in a closed form. The core-shell nanoparticle supports midgap bound states located at both interfaces due to band inversion. These states are robust since they are topologically protected. The energy spectrum presents mirror symmetry due to the chiral symmetry of the Dirac-like Hamiltonian. As a major result, we show that the thickness of the shell acts as an additional parameter for the fine tuning of the energy levels, which paves the way for electronics and optoelectronics applications.
References in corpus (7)
- Topological Insulators
- Topological crystalline insulator states in Pb(1-x)Sn(x)Se
- Volkov-Pankratov states in topological heterojunctions
- A 3D topological insulator quantum dot for optically controlled quantum memory and quantum computing
- Optical response of a topological-insulator--quantum-dot hybrid interacting with a probe electric field
- Spherical topological-insulator nanoparticles: Quantum size effects and optical transitions
- Electric control of the bandgap in quantum wells with band-inverted junctions